to balance the sliding door, you need to adjust these 3 points:

- the rear door lock mechanism/hinge -> to level and/or moving the rear *up
and down*
- the bottom roller attachment -> to level and/or moving the front *up and
down and in and out*
- the top roller attachment -> to move the top *in and out* to reduce
lateral drag.

it's a 2 persons job but you can do it with one if you use various support
under the door (I began with a combo bucket and 2x4 with different
thickness) but it's easier with 2 bottle jacks with 2x4 and you can adjust
at minute increments.

Do not adjust all 3 points at the same time. I adjust one point at a time
and move to the next and may be going back to the previous and so on.

have fun...

dan