i had a problem like this before! but mines was a easy fix though it was in a integra! which i replaced the clutch/slave/master cylinder. brand new. how it is from the shops i installed them, but same scenario as yours. and bleed til I gave up. So i thought since i took all the slave/master cylinder out im sure theres alot of air in them and so i took out the master cylinder again! and examined the differences from teh stock mcylinder and stock mcylinder. the differences was the nuts/screws that you adjust on the master cylinder, was off bout 1/2" away from how the stock mcylinder was, so i kinda messed with the adjustment nut bolt. got it to where it sits ressembles to stock and the installed the mcylinder back, bleed it again! this time I borrowed a buddys air compressor bleeder, and within 10mins or so wabammm i was back on the road!

well thought i share my scenario with you, hopefully it might give u some help ..