Hello, I went with converting the rear drums on the 1970 240Z to the 1978 drums for the supposed "stronger spindles" and double brake cylinder. Fun fact the flange that bolts the spindle to the half shafts is not interchangeable btwn the two.....splines don't line up, that's for another conversation!!.......anyways, I got a new 8" booster because of the new rear brakes and upgraded double piston fronts. I have a 7/8" master but bought a very used 15/16" from "FleeBay" (EBay) to handle the extra fluid demand. Is there a secret society I can join to get a rebuild kit for the 15/16" and with the rear valving on the 15/16", I understand I need to add a "stopper" piece for the rear drums. Question is, with the valving from the rear bowl of a 7/8" master cylinder, will it fit in the 15/16"?