Help please-- 02 seats same as what other years?

[Hunterford]

Hi everyone...my brother (until recently) ran a custom upholstery shop. When he closed it, I bought a quantity of brand spanking new takeoff seat covers, mostly from GM trucks, and mostly 2002 models. Can anyone tell me what years of trucks these would likely fit (given the same seat configuration)? Is the break between 98 and 99?

Also-- is there any internet resource that can decipher part numbers? Each of these covers has part numbers, but I don't know how to figure them out. I have several buddies who want a set of these covers, but I want to make sure they are going to fit.

ANY help would be greatly appreciated. Thank you very much. LL