Well the OD trans and gas tank, you must be talking about the trans tunnel fabrication, and the gas tank must be the filler neck or the box clearance to the tank. Those should all stay with the frame that they were born with, but if those end up being my biggest issues, I'm golden. The trans tunnel could come from the donor pickup as well as some floor patch panels that have been so primitively repaired in the past. I haven't even decided that I'm going to do this, and I'm already getting fired up about it.