1972 C20 Custom Order Questions

[neteng01]

Hello Everyone,

Awesome board and great information, just to say it.

I have a question that I have been trying to resolve for a couple weeks. I traded up to a 1972 C20 Custom Camper recently. I am starting the whole restoration process and have a few questions as to the original equipment on the truck. The VIN and all stickers match on the vehicle, the codes define the C20 and all the major items, including color, trims and accessories. The 2nd owner I got it from removed the dual battery configuration and I want to restore it back to original config, but the original motor was swapped with a crate 350. I can't seem to find any details on the dual battery config, what it looks like or how to restore the setup.

I am also trying to establish if the 400 CID V-8 called out on the equipment list is actually the 402 Big Block, and why the Model# does not match any listing here I have found for my model and year. It may be a custom order from the factory but it is very hard to tell for me so far. I have attached the pics of the glove box SPI, Placard and Door Jam Sticker for reference and a shot of the actual truck. Its an awesome truck and I am having a blast going through it, but I want to be sure everything is up to Par on the details. It does have Big Block motor mounts in it which is why I am wondering if the OE was the 402 Big Block.

Any help would be greatly appreciated, you folks are the experts from everything I have read and need some expert info.