My '98 had a stripped down plain-jane interior when I got it. I hunted down all the plastic pieces from the up-scale & the early trucks (Which came with all the plastic trim. GM cheaped out on the later models.)
The pieces I found came from several different trucks, in several different colors. You'd never know unless I told you. (You know now! LOL!)
This is the procedure I used.
I recommend SEM.
This my interior in my '98. Don't look at the seats (!) Those are reupholstered. What this pic is for is to show the back panel under the rear window. It used to be dark blue, dyed to factory color. In the pic, the 'B' pillar pieces are not yet installed, but they were tan. They came out the same as the back panel.
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Dye is NOT paint.
The dye does not sit on top of the plastic, like a paint. It soaks INTO the plastic.
The key to properly dying plastic or vinyl is prep. I can't emphasize this enough!
I like to scrub down whatever is being dyed with a 10% vinegar/water solution first. This will remove the oils & ground in dirt.
Once they're dry (next day), I'll wash 'em down again, with T.S.P. (Tri-Sodium Phosphate) Paint/Home improvement stores will have this. House painters use this to neutralize oils from hands around light switches & stuff. Comes as a powder. Mix as directed on box. Use a good stiff bristle brush for both of these procedures.
Rinse, rinse, rinse, with cold water. Let sit to dry in the sun, or somewhere warm overnight.
Do not touch anything that is gonna be dyed, after these steps, with bare hands. Use 'throw-away' rubber gloves, or touch only where it won't be seen. The oils in your hands will effect the adhesion of the dye.
Knock down parts to their smallest pieces. Makes for a better finished job, & requires less masking off of pieces not to be dyed.
Hang small parts on coat hangers or wire.
At this point, you can use a product called 'Vinyl Prep'. (SEM product, check their website.)
http://www.semproducts.com/product-catalog/prep-products/vinyl-prep/
This works, too.
http://www.semproducts.com/product-catalog/prep-products/sand-free/
Both are available @ O'Rielly's.
This softens up the first layer of plastic. The dye will react with this, such as a catalyst for fiberglass. It allows the dye to soak in, then it 'kicks' to make the plastic hard once again. The dye is sprayed on while the vinyl prep is wet.
Several light coats are better than a couple of heavy ones. Drips will NOT be able to be sanded out.
Let dry for at least a day before handling.
Any rough texture can be knocked down after a few days (Want to make sure that the dye has cured well) with a bit of newspaper, which is the equal to about 4000 grit sandpaper. Don't have to rub, just a nice easy wipe! Follow that with some 'interior detailer' to give a nice semi-gloss finish.
Good luck.