Usually there is a bead of that black goo that holds a plastic sheet "moisture barrier" in place.
Seals the edge of the sheet around the holes in the door for accessing window regulators, etc under the inner trim panels/cards.
Yea, that stuff is ...

...gets on everything.
See if you can get ahold of some Prepsol from a painter bud to get it off you.
On trim try it on a hidden piece first to make sure it doesn't also remove the color.
Paint thinner will work, too but same disclaimer if you try using it on the insides of yer truck.
Heck, gas will break it down to get it off you.
On yer clothes try scrubbing with Gojo type cleaner before washing.
If the plastic is gone from under the door panel it's been opened up before.
Big surprise on our old rides.
Try to remove all of the sticky, gooey residue with a thinner soaked rag while the trim panel is off.
At the dealerships I've worked at most cars get those plastic bag throwawayable seat cover thingys immediately upon hitting the service drive.
You may not be taking yer Luv to Chevrolet
Having done a bunch of TSB replacements on 98 Caravan/Voyager door lock solenoids I can understand yer situation.