Decided to share this here as it might be useful to some. Around this time last year I decided to narrow a Ford 9" for my 67 Firebird. Although not a g-body, the same principles apply. Also, if anyone is interested in fitting the LS-1 brakes on their Ford rear....read on.
Before I get into it I should mention that unless you have a Ford 9 (or some other rear-end) laying around, I did not really save much over buying a manufactured to fit housing. Also, try to figure out the offset needed for the brakes you will be using first. This will save you a lot of time and frustration later on, trust me.
I started with a late 70's ( I believe) Ford F-series truck 9" housing. I traded an unused home gym for it, so in my mind it was basically free.
Step 1 was to compare the 9" to my old 8.5 GM housing. I set them up on jack stands and later built a jig out of 2x4's to line them both up. This allowed me to compare center to center and overall length. You will most likely end up cutting uneven amounts off to match the pinion centerline. Because I had leaf spring perches, it was easier to match my pinion angle pinion. On a g-body rear, I would use an angle finder to compare the angles when welding your perches and control arm brackets back on.
Before I get into it I should mention that unless you have a Ford 9 (or some other rear-end) laying around, I did not really save much over buying a manufactured to fit housing. Also, try to figure out the offset needed for the brakes you will be using first. This will save you a lot of time and frustration later on, trust me.
I started with a late 70's ( I believe) Ford F-series truck 9" housing. I traded an unused home gym for it, so in my mind it was basically free.
Step 1 was to compare the 9" to my old 8.5 GM housing. I set them up on jack stands and later built a jig out of 2x4's to line them both up. This allowed me to compare center to center and overall length. You will most likely end up cutting uneven amounts off to match the pinion centerline. Because I had leaf spring perches, it was easier to match my pinion angle pinion. On a g-body rear, I would use an angle finder to compare the angles when welding your perches and control arm brackets back on.