Phil, regarding the door relays; I've read about that in other threads before.

Were the relays installed left to right and right to left at the factory and GM just never figured it out?

Did someone work on your truck in the past and get them mixed up?

This seems to be pretty common. What is the explanation for multiple / all trucks having the relays reversed?

1950 Chevrolet 3100 (Ol' Roy)

1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)