I've always had a soft spot for the Malibus, and growing up in the 80s, thought t-tops were the coolest thing someone could have on a car. Our neighbor had a t-top cutlass, and I was always a little jealous our 'Bu didn't even have that option. Fast forwarding some years, I started building my current Malibu project and at some point got the bright idea to graft on a t-top roof and live out that childhood dream.
Before cutting up the car, I did some research and learned while the bottom 90% of the A pillars are the same between, the B pillars are completely different and that there are two different B pillar designs on the t-top cars. When it's done, I want the car to look completely stock, so I knew that I would have to do some custom fab work to make it all fit. The donor roof came from a 1986 Monte Carlo.
This picture shows my clean, 1979 tub, braced and ready to go under the knife.
I started by cutting the A pillars roughly half way down and took a sawzall to the entire roof right in front of the B pillar. No turning back now!!
Next, I cut the front face off the B pillar, leaving the quarter window frame intact. I also cut the inner roof structure back to fit the cross brace on the t-top roof and notched the remaining roof skin to reach the inner structure to weld it together.
At this point, I was able to test fit the donor roof section into place. I was starting to feel better, like I might actually be able to pull this off.
I tacked the A pillars into place and went to town fully welding the donor B pillar to what was left in the Malibu. I measured 100 times for each weld to ensure the roof was square and that all dimensions were correct to the templates I created before I cut the roof off the Monte. The bracing lined up almost exactly between the two, and the biggest challenge was matching up the inner structure of the B pillars. The factory Malibu pillar ends about an inch further back than the Monte, meaning the Monte B pillar is more upright than the Malibu. The seatbelt mount was put in the correct position for a Monte to allow less customization required on interior parts. The picture below shows the inside after welded, along with my garage pal. He's now old enough to understand what tools are what (and how to get beer out of the fridge) so he makes a great gofer, and loves to spend time in the garage.
I was going to weld the two halves of the A pillars together, but could not for the life of me get either one of them straight, using the windshield and side trim as a guide. I decided to spring for new A pillars, and found that the front header panel was reproduced as well. Mine didn't have any holes, but did look a little crusty even after being dipped. I drilled out what felt like 200 spot welds, most of which in the header, to remove the components and welded the new ones in. I was amazed how much seam sealer was used to cover questionable welds at the base of the A pillars. The header had a spot weld every inch or so, and the base of the A pillar had maybe a half dozen total holding it to the firewall, some of which popped off without drilling out. I put in some extra welds both on the outside and inside for good measure. For aftermarket parts, I was actually impressed with the fit. Only the A pillars needed the fender hole oblonged to align properly, and that may be because they aren't actually meant for the car.
With the structural work done, I changed focus to working on the frame. The tub will be going in to be acid dipped this winter, and when it returns, I will have the cosmetic work completed. I will pay someone to do that, as it's above my abilities and available time. The bottom of the B pillar skin will need to come in about 1/4" to match the character line found on the Malibu. The steel around the quarter window will be finished, removing the drip rail and closing off clean to the window. The roof transition is different between the two, so I will use the sharp crease found on the t-top roof all the way to the C pillar.
In all, the conversion isn't too difficult. The key, as with most in-depth projects is to take your time and wear out the tape measure before welding things together. It's always easier than taking it back apart and redoing it!!
Before cutting up the car, I did some research and learned while the bottom 90% of the A pillars are the same between, the B pillars are completely different and that there are two different B pillar designs on the t-top cars. When it's done, I want the car to look completely stock, so I knew that I would have to do some custom fab work to make it all fit. The donor roof came from a 1986 Monte Carlo.
This picture shows my clean, 1979 tub, braced and ready to go under the knife.
I started by cutting the A pillars roughly half way down and took a sawzall to the entire roof right in front of the B pillar. No turning back now!!
Next, I cut the front face off the B pillar, leaving the quarter window frame intact. I also cut the inner roof structure back to fit the cross brace on the t-top roof and notched the remaining roof skin to reach the inner structure to weld it together.
At this point, I was able to test fit the donor roof section into place. I was starting to feel better, like I might actually be able to pull this off.
I tacked the A pillars into place and went to town fully welding the donor B pillar to what was left in the Malibu. I measured 100 times for each weld to ensure the roof was square and that all dimensions were correct to the templates I created before I cut the roof off the Monte. The bracing lined up almost exactly between the two, and the biggest challenge was matching up the inner structure of the B pillars. The factory Malibu pillar ends about an inch further back than the Monte, meaning the Monte B pillar is more upright than the Malibu. The seatbelt mount was put in the correct position for a Monte to allow less customization required on interior parts. The picture below shows the inside after welded, along with my garage pal. He's now old enough to understand what tools are what (and how to get beer out of the fridge) so he makes a great gofer, and loves to spend time in the garage.
I was going to weld the two halves of the A pillars together, but could not for the life of me get either one of them straight, using the windshield and side trim as a guide. I decided to spring for new A pillars, and found that the front header panel was reproduced as well. Mine didn't have any holes, but did look a little crusty even after being dipped. I drilled out what felt like 200 spot welds, most of which in the header, to remove the components and welded the new ones in. I was amazed how much seam sealer was used to cover questionable welds at the base of the A pillars. The header had a spot weld every inch or so, and the base of the A pillar had maybe a half dozen total holding it to the firewall, some of which popped off without drilling out. I put in some extra welds both on the outside and inside for good measure. For aftermarket parts, I was actually impressed with the fit. Only the A pillars needed the fender hole oblonged to align properly, and that may be because they aren't actually meant for the car.
With the structural work done, I changed focus to working on the frame. The tub will be going in to be acid dipped this winter, and when it returns, I will have the cosmetic work completed. I will pay someone to do that, as it's above my abilities and available time. The bottom of the B pillar skin will need to come in about 1/4" to match the character line found on the Malibu. The steel around the quarter window will be finished, removing the drip rail and closing off clean to the window. The roof transition is different between the two, so I will use the sharp crease found on the t-top roof all the way to the C pillar.
In all, the conversion isn't too difficult. The key, as with most in-depth projects is to take your time and wear out the tape measure before welding things together. It's always easier than taking it back apart and redoing it!!
