A LOT of the work was done with the frame upside down on the jack stands. In this pic you can clearly see some of the holes being eliminated. The ones in the bottom of the crossmember were left to aid in drainage as water can get in thru the lower control arm mounting locations.
In this pic, you can see the location I chose for the fuel lines to come thru to the engine.
One of my more sneakier tricks was to bend and install a section of stainless tube INSIDE the frame, carefully positioned so as to give the air bag a wide birth. The red part of the fitting goes to a short section of flexible braided hose pointing towards the back of the car. The other end goes to the bulkhead fitting shown in the first pic.
Finally, the boxing sections were ready for pick up, and no time was wasted fitting them to the frame.
Initially, relief cuts were made, and the "ears" were bent out to match the shape of the body mount area and welded up. This has since changed. Now, that shape actually extends down to the bottom to make access easier.
So, how do you make a straight section of 1/8" plate with a 90 degree bend in it form a curve? This is how...