'77 Suburban Slam- Could use some insight...

[SRD art]

Looking for squarebody insight- I'm starting on my '77 Burb project next month, rendering and Photoshop for illustration. I want it to be as low as autocross trucks with aftermarket chassis’, however for now my budget requires I use a factory frame and front cross member. If my estimates are right that should end up about 4-5" of ground clearance under the center frame rails.

Building a different 1/2 ton chassis I already have drop springs and drop spindles and I plan to section the front cross member 1.5”, should be about 7.5” front drop (?). Out back I’ll do a C-notch and axle flip + whatever to end up with a 1” rake.

To me shorter tires look out of proportion against a Burb’s big butt so rolling stock is 275-45-20 on 20x10” wheels with 5.75” BS all around. Engine is a 454 BBC with roughly 425 hp and 550 ft lbs.

Mod/Fab questions- I’ll do different front wheel tubs and a 3 u-joint steering shaft to clear the raised upper arms. Out back I’ll raise the rear wheel tubs about 3” and the floor above the pumpkin 2” or more as needed. My research shows the trans tunnel should be good but I can modify that to be taller too if needed. What other fab work should I anticipate having to do?

Thanks for any insight!