I have some broken studs coming out of the rear quater extensions. I want to replace and reuse the 1/4 extension in my restoration, is there a supplier out there for these studs and also the nuts. It looks like they are potted into the aluminum casting and will need to be drilled out. Any one have any tricks or tips out there? This must be a common problem that someone must have dealt with it. I was thinking of drilling and tapping with threaded rod but was hoping for a better solution.

Thanks