Your truck is the same as mine!
Yes, there were several different trim levels each year, the door panel you speak of came off of a LX trim level truck......they had the chrome door handles, and chrome tail light trims and the extra sound deadening inside the cab, so on and so forth.
You can install those on your truck though......I just put the chrome grille and tail light trims and door handles on my regular cab 1989 truck. Here's some pic's of it.
I have a chrome bumper for it also, I need to install it!