Can’t help on the hood question. Partial answer for your base plate question below. I don’t have the 426 or six pack numbers handy. I also can’t help if you’re asking about the Adaptor Ring (the big part that the rubber seal attaches to).
4-Barrel Shaker Bases
Engine Part# Throat Depth*...
Top pic auto, bottom pic manual. Do the have ash trays at the rear or a slotted area for seat belts?
With seat belt slot is 70-only E-body
With ash tray is 71-74 E/B-body
I’m looking for a. Nice 70 E-body 4-speed console if you’re selling.
A couple of months ago I tagged along with a friend on a trip to visit some of the VP filming locations. He drove his U-code 70 Challenger from WI to NV and back. Fantastic trip. We posted some pics here:
Vanishing Point 50th Anniversary Run in Cuda & Challenger General Discussion...
Yep, cleaning off the old carpet residue turned out to be a real PITA. I was about 2 min into the job when I decided maybe repros would be the way to go. Saw the price and went back to work cleaning my origals!