[RyanAK]

Old65C10 - thanks for the continued interest and advice. I plan to do some significant sound deadening eventually but don't have the cash and/or time to dig into it now. That butyl flashing tape might be a good and inexpensive way to get something on the floors, quarters and roof (when I go after the headliner...) in the short term. Have you used it? The remaining 'boom' seems to be located in the rear.

I'd love to get the drive shafts balanced... I'm still searching for a shop within a reasonable distance to get to.

Tires... when I can spring for new wheels and tires I'm hoping that does a lot to improve ride/noise. These 235/75R15 Toyos that have been on the truck for who knows how long may be a significant contributor. I may spring for a balance if it looks like wheels/tires are going to be way off into the future.

Stock dual exhaust seems in good shape. Nice and quiet and exit at the corners. I could see how a deep, loud exhaust could contribute to serious cabin noise, especially with that large, uninterrupted expanse of floor acting as a drum head...

Getting new Bilstein 4600s soon. Doesn't feel like it needs new shocks, but they look like they've been on for decades. Hope for a ride and noise improvement there. Especially for the money. Suspension bushings look ok... they're on the list for replacement eventually. Body mounts I'm going to tackle while the truck is at the body shop and on a lift for the cab and tailgate support rust issue. They're smooshed.

Door striker bolts are an interesting thought... The driver door sags a bit and I have the pin/bushing kits for all doors and will adjust the hinges/alignment, but the striker never occurred to me. I'm not sure if the '78s had the plastic bushing... and the doors close tight... I am going to replace the weatherstrip on all doors and tailgate. Those pieces are currently in my LMC shopping cart along with the cab and tailgate supports that need replaced to pass inspection. Maybe I'll add the striker bolts too...

Great thoughts all around. Thanks!!