Most engine parts for Chevy car and light trucks will fit from the late 60s to the mid 80s. Many body parts from light (10,20,30 series) Chevy/GMC will work from 1968 thru 1972.
acctually its 1967-1972 where most of the body parts will fit, but there was a slight change in the dog house and maybe the cab from one year up to 1972. I believe it was just 71 and up, but it may have been 70 and up. They where very small changes that can bearly be seen at just a glance. One notable change was in the front of the hood. some of them go straight down, and some of them when down and then beveled forward for about a half of an inch to meet the grille. Another thing that i believe was different was me and my dad looked a 71 4x4 years ago, and the doors did not fit snuggly. the door stuck out slightly like it wasnt shut all the way. There was about a 1/4 inch gap all the way around both doors. We looked them over carfully and could find nothing that had been done wrong when mouting them and just blew it off as maybe a door off an earlier truck and that was maybe one of the small changes that was made. Although it did fit tightly, just looked goofy.
But most other parts i believe are completely interchangable. Best thing to do, like if your needing new finders for example, and would rather find some in a junk yard rather than buying new, just look in an LMC truck book(LMCtruck.com) or year one book and look for your part, and see which years are the same part number as your truck.
It would depend on which parts. Give us more info.
It depends on what parts you are looking to replace, mechanical or body parts. List the parts you are looking for.
1971 and 1972 for sure, possibly 1967 to 1970 also.
1995-1997
Most parts are interchangeable
1988 to 1991 most parts are interchangeable - body styles an other things changed after 1991
Almost no parts are interchangeable.
The distributor and the oil filter.
From 1988 to 1999 will ALL interchange
1982 - 1994 (early year models).
1975-76
1988 through 1999 parts are the same, Give are take a few things.