Lenco discs are anywhere from .058 to .062 when new. They get to .052 or so they are worn out. They get to .050 and they are JUNK. Clutch pack clearance is .080-.100

You should never have to run the air pod down on an air shift trans to tighten it up. If you do this you are taking out free play, which tells you the clutches are toast and running it down and taking up clearance just wears whats left faster.

When setting up clutch pack clearance, like any other trans it's floater, disc and ends up floater and then wave spring. You want as many discs as possible, but sometimes you have to stack an extra floater to get clearance right if another disc won't fit. They also make all different floater thickness for setting clearance.

On another note, if the car is 60footing better with a slipping trans, this confirms what I told you earlier about hitting the tire way too hard and wadding it up