Monogram bottom freezer door adjustment

[joeswamp]

So my ZICS360NMBL GE Monogram bottom freezer was starting to have a tough time in hot weather and so I decided to replace the freezer door gasket.

After replacement, I noticed that there is now a huge gap at the top of the freezer door, like 1/8". I guess the door has kind of a tilt to it, and the old freezer door gasket was squashed pretty flat at the bottom. Since the new gasket isn't all squashed, there's a gap at the top. I'm not sure if this gasket is magnetic. If it is, it's about the weakest magnet ever.

I found the service manual of this fridge and there doesn't appear to be any provision or procedure for freezer door adjustment, it's just supposed to be perfect. The door attaches to two drawer slides with eight screws (four per side). I suppose its possible that these drawer slides are worn, there is a little play if I lift on the door. Unfortunately the RH slide is no longer available, while the LH slide retails for $490.

Has anyone worked on these and experienced this problem? I guess I could fit washers between the slides and the door to try and level the door, has anyone done this successfully?