oilslick, with a loose wheel from each car check the ET number (offset in mm) to see how they compare. The best scenario is nearly identical numbers so there isn't an interference with brake calipers, suspension components or fenders. Also, compare the size, seat contour and thread projection of the lug bolts for each vehicle's wheels. If all the lug bolts match, then you can use the best lug bolts for mounting the 1993 SD wheels on the 1987 SDL.

__________________
Fred Hoelzle