yeah, you'd want to keep the C pillar where it is and add a D pillar a few maybe 6-8" aft of the c. when I look at my wagon, it seems that the rear passengers noses are about flush with the front edge of the C pillar....maybe if you added a strip of material between the back of the C and the front of the D- using the factory D relocating forward- you could maybe even keep the tailgate with the D pillars, rolling window included. the rear frame can be cut down by about 10" without having to do any more than add a new flat crossmember(bumper) when you cut the frame horns and factory rear brace off. the gas tank on my 77 is about 11-12" in from the rear face of the rear brace. there is a body mounting point back there, but if you're bobbing, you wont need em.

