65 Chevy C10 rear drum brake woes. please help.

[Agv63]

Bleeding the brakes with engine shut off should still bleed correct at the rear with pushrod in original location. It works like manual brakes, Its when the booster is active when the pedal feel changes, then the location must change. If it bleeds thru but no brakes it could be that someting is limiting slave cyl travel, like those 2 ears on the backing plate to stop piston popping out. It could be those small pushrods that connects piston to shoe is on short side, Piston depth can vary from different suppliers. Orthe original drums is worn to such a point that normal thickness shoes is running out of travel to make contact, coming back to piston hitting those stoppers, to verify a long bolt can be used to make new pins but longer, cut head off ,and a slot cut in , lenght can be choosen where needed and another cut and a rounding be made on other side.

Cheers.
Adriaan.