foam sanding block to rough up the surface of the steel tube (to provide some 'tooth' for the spray paint). I believe the sanding block was 400 or 600 grit, nothing too aggressive. For paint, I used Rustoleum 7515 High Performance Enamel Aluminum. It happens to be a very close match for the silver color that Honda uses at the factory.
Here, the Givi base plate has been attached with M6 Allen Head bolts. For vibration resistance, I used Nyloc nuts as well.