I have a mud truck that has no rear brakes, just front. I have the rear blocked off with a plug and the front is bleed and hooked up. It is a 94 s10 blazer master cylinder with 80's 3/4 ton front calipers. Calipers and lines are new The brake peddle is solid as a rock and will bleed but there's no brakes. Is there a certain way to block off the rear with out this happening? I think it must be doing this because of the rear being plugged off.