No offence KDrown. I've never seen anyone use nub wheels with clip caps. I don't recommend that to the poster.
To the poster: If you want original 15" rims for your truck, you search and buy original rims from somebody. As far as wheels with hub cap clips that fit whatever caliper you have you need to measure, make a go no-go gauge or trial and error. Wheels available were 15, 16 and 17.50. GMC or Chevy, same wheel. They are narrow and tires are sometimes pricey. There's a brazillion choices without clips, 6 on 5.5.
I have used the ever popular Chevy 10 slot rally Wheel over calipers on 55.2-59. They look good with trim rings and top hat cap. Around 1973 era. 7 wide and 8 wide. Look good with the ever popular 31x10.50R15 tire. Ebay and Craigslist for the wheels. Also there is a 5 slot Chrome rally.
I am not guaranteeing they will fit your calipers. But many were used with disc brakes.
