If I unplug the regulator it will run and not blow fuse but won't charge of course and when I plug the regulator back in it blows fuse. A local repair shop said it wouldn't be the regulator and I don't know cwhat else it could be'

A bad ground could cause this or a plain old short in the wiring. One other thing if a wire was replaced and not matched in gage this could also blow a fuse.