not all governments act the same, but if the number plate is gone the engine number may be acceptable

I'm going to opine that the rusty wing is a replacement - potmetal pits but doesn't typically surface rust

to make the paint you need a modern formula, not the original. Both the base and pigments differ today, so an original formula is of little direct use.

I don't think Customs and Supers had the same trim level.

Budd had a lot of experience in all-metal construction from streamlined corrugated railroad cars. The doors were obviously a separate contract from the bodies (wasn't Briggs doing the 41 - 2 bodies). The investment in tooling to convert the doors would be much lower than changing the big body stampings

You're right - both 41 and 42 doors have a Budd plate in the front passenger door where the trim panel covers it.

I recall an article where a Packard ex-employee talked about mixing goat hair into trunk paint. I would think a synthetic flock would give much the same look. My 22nd Junior trunk was a shade of gray very close to Rustoleum Smooke Gray, and the original trunk shown looks similar.

The hogshair carpet info I've seen does match with thin ribbed material running front to back.

I don't have a photo, but the trunks of the preceding 160's and the uper Clippers are much simpler than many restored cars look today

bit o' Buick in the side trim

It's a non-metallic beige - I found a decent match at the hardware store by snooping through the stock