Will - Those cargo panels behind the seats are the most valuable part of the whole interior, basically. That and the dash/center console.
Also, for some reason, the center vents and clock are fairly valuable. Apparently, ricers can't keep from breaking those parts when they want to paint them loud, annoying contrasted colors.
The '88 HF's doors are lighter than any other door, and the front sway bar (sorry, I thought rear at first.) is hollow, but stiff, thus lighter. Auto cross racers find value in these parts.
Also, if you can get the ball joints and tie rods loose, Ben might need those knuckles... LOL.