I'm still sorting out how retrofit the 2015 fuel pump into the 87 tank... it already has a baffle.. but the opening is only 3", and the main reservoir with regulator is 3.15 ish.. plus the upper plastic parts that houses the regulator ...so if use the whole assembly, this is what I think would work out
Basically the octagon shape plate will get welded to the tank, and has the base for the oe sealing ring, a spacer since the o-rings is so thick, and the top ring plate to sandwich it all together. If I could find a flat gasket that fits the pump, that would be better since it could be made out of the same sheet of steel.
Kinda stalled out since I'm trying to source a high hump tunnel.. struck out at 3 pick n pulls.
If anyone has a line on a 81-87 truck or 81-91 crew cab high hump tunnel pm me. Also looking for pictures of 4x4 suburban floor pans to see if that could work. Hours of searching and can't find a single suburban high hump picture on the Internet.