Front window wont roll down all the way

My son and I are restoring a 57 BelAir sport coupe. We have new window class and internals (regulator, etc) in an original door. Passenger door was a breeze - no issue. Driver's door is hard to roll up and down, and when rolled down the rear of the glass sticks up out of the door about 1".

Any ideas on what we did wrong?

...thanks.

Are the rollers still in the track?

Could be worn rollers, worn fuzzies, or a worn regulator. If it's all new stuff, you may have an adjustment off. Have you gone through what's in the shop manual?

I assume you adjusted the short slide per the manual/ instructions. Given that, another possibility I ran into on my current build (56 Chevy HT): the new regulator that came with the power windows did the same thing when mounted per their hole template. I had to slot the mounting holes and rotate the regulator to get the window to level.