Crazy brake problem...help?

[nevaland9]

Ive got a 91 S13 with stock brakes just SS lines, so the other day im bleeding my brakes and my little brother grabs the wrong bottle and pours about a shot glass of power steering fluid in my BMC, i stop him in time from pouring anymore in.

I get a rag and try to absorb as much as i can but i guess i didnt do a good enough job, within a week after a night of spirited driving the brake pedal gets super stiff and the brakes start locking up very easily. and on hill the car wont roll forward or backwards. so i bring the car to my shop and put it up on a lift and sure enough the pass. rear caliper piston wont go back in, so i take it off and try to screw it in with a tool and it stops about 3/4 ways and refuses to move, but when i release pressure form the caliper is goes back in with ease.

So i figure is something in the line and the power steering fluid messed up the BMC, so i put in a new BMC and flushed the fluid out for new DOT 4 stuff but ive still got the same problem!?!

i havnt driven her enough to see if its any better or worse but i think its just wee bit better if anyone has any idea whats wrong here dont be shy