Went to the junkyard and all they had were two 1990 LA1Z 4-door Jettas. I yanked the one from the later car (had about 110k) and installed it in my GLI without checking or adjusting the pushrod length against my master cylinder. Observations with new booster: 1.) FAR less effort required to apply brakes. With a good booster in the car now, I realize just how ridiculously hard I had to stand on the pedal before. 2.) Pedal height is much higher at initial braking point, probably 50% higher than before.
Pros: less effort to apply brakes, pedal height higher
Cons: pushrod length unadjusted
Vehicle:
Volkswagen Jetta
Mileage: 110000 km