What to put between painted body panels?

[mc1984ss]

I am about to reassemble the front end on my Nova. I am looking at the painted joints that will be overlapping such as the inner and outer fenders and the inner fenders to core support. I had thought about using strip caulk / dum dum in bed the panels. I figure this will prevent rattles and will offer a little cushion in between the panels. Any thoughts or experiences? Thank you!

[Vimes]

I don't think I'd bother with it, but if I were going to put stuff to keep noise down between steel bolted to steel I'd use 3M™ Squeak Reduction Tape 5430. One place I would put this is anywhere on the interior where plastic meets metal, and where the dash meets metal.

https://www.3m.com/3M/en_US/p/d/b40070582/