I share your concern about rivnuts.
One job for the winter last year was to replace all the rusting bolts on Tarka, the rubber was bulging. To eliminate the corrosion caused by different metals I was planning to source "peek" screws and nuts. Skiffy sell them. Given there is no real load on the screws and their multiplicity I felt that they would be fine, and as a fibre reinforced polymer, they could not cause corrosion.
Instead I bought a car without running strips.....!! [/quote]
PEEK screws would be a good solution, albeit expensive especially if carbon fibre reinforced. As a Technical Manager for the UK company who manufactured PEEK I used to deal with a Swiss company who made carbon fibre pultruded rod then shaped to make a screw thread. They were incredibly strong and would take a huge amount of torque, alas they were incredibly expensive. I have often thought that the lubricated grade of PEEK would have been ideal for the sliding pillar bushes.
