Been doing a bit more digging into the truck. I thought the engine might have been replaced because it was blue but it does look to be the original. The quadrajet carb kind of threw me off as well.
The date code on the side of the block is a bit weird, but the block is a 2536030-318-4 and the stamping on the front EW318R27400064 indicates it is a 69. I'll have to check out the vin pad to be totally positive.

Other than that, I've fixed the trans filler tube leak, changed the motor mounts and swapped the wheels around. Need to fix door locks, and make some rails to mount passenger seat (or put in a bench).

I'm really tempted to put in the 451 stroker motor I'd intended to put in the belvedere....