Hy Fourbrads, the six stud on 5.5" bolt circle has been around for years, even before your truck was made. Things like metrification, and disc brakes have changed the wheels design quite a bit. I'm not sure what "modern" wheels will fit, but any GM made 1/2 ton up to 1970 should fit, Toyota pickup wheels should also fit if I remember correctly, I know I'm being general again, but I hope that helps.
