[njsteve]

3M Strip-Caulk is the official name of the stuff. It is 3/8 thick by 1 foot long strands of black rubbery, non-hardening caulking that is designed for auto body seams and a million other uses.

http://www.autobodytoolmart.com/3m-s...8-p-10395.aspx

The center section did not have much of any adjustment. The main adjustment was in the end caps both outward to the sides, and twisting to fit the quarter line. Adding the strip caulking around the stud mounting bosses is what really helps the fit. It squashes down flat but that 1/64 of an inch may be all that it takes to get the spoiler end caps to align properly and create the right gap. It also waterproofs the large mounting holes.

Also, do not crank down on the mounting nuts too tightly. It is very easy to break/crack the spoiler mounting bosses on these old fiberglass pieces.