brake master cylinder and blocking the rear line?

[poshatch]

ok so i have to block off the brake bias (where the line for the rear connects) because im going to be running a hydro brake. so i took a spare line and cut it and made it short and melted the end of the line so that fluid wouldnt come out and screwed it in just like a regular line

i had a z32 15/16 bmc in my car for awhile, then one day it lost pressure

i opened up all the bleeders all the way and it wouldnt pump out fluid...

so im guessing the seals went bad or something because it should be gushing fluid

i swapped a stock 7/8 bmc back into the car and it was allowing fluid to flow, ive been trying to bleed it but its not gaining pressure at all so im assuming that i CANT block it?

and i guess this is explained by the fact that hydro ebrakes that are sold out on the maket use a ss line to go from the rear to the master cylinder they use, which supplies it with fluid and also allows the rears to be used in the bias functioning as a normal brake set up...but then using the master cylinder to put pressure on the rear brakes and not back towards the bmc (if this is true im going to kick myself for not doing more research)

is this correct and can anybody verify this?

its been really frustrating that i cant just block off that line and use the set up ive been using and i need to get this figured out asap