Thanks for that, sorry for being a bit dim here though, but how do these "Well Nuts" work? Do they just hold/grip themselves in the appropriate sized hole whilst you screw the bolts into them?rubber well nuts
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yeah basically. they are a push fit into the hole, and at the end of the rubber there is a threaded insert. as you tighten up the screw it pulls the insert towards the rear of the hole. they are mainly used for fibreglass ( kit cars/caravans etc ) for mounting lamp assemblies, but they do work well for door mirrors, Ive used them