I bought a 1982 GL1100 and the mirrors fold in when I go above 30 mph. So I bought a set of replacements. Installation seemed straightforward: remove two Philips head bolts, install damper and new mirror, install bolts. However, the bolts just turn and never tighten when reinstalling. I thought there would be a stationery threaded element inside, but there must have been a nut instead which has fall. How do you get in behind the speaker on the faring to install the mirror bolt/nut?