You should have a ground wire or strap from the engine head (which is the ground from battery) to the fire wall (body). Clean all contacts and use dielectric grease at ends. I see no reason to set grounds to master cylinder.
Thanks , I will pick up some dielectric grease . This car did not come with a engine to firewall ground strap . I went to the MC bolt because i wanted it on a solid firewall bolt , and i didn't want to drill any new holes .
