Windows don't up roll up/down easy - need input please

[lks dcvn]

Bought a project truck last winter and it has all new window felts, rubber, etc. in the cab - and especially the doors.

It is very difficult to roll the windows up or down...as in feels like it will break the regulator (or the glass)

I took off the door panel and sprayed the track down with White Lithium Grease - no luck...didn't change a thing. Not sure where it is sticking - appears to be the vertical track that the windows slide down/up (not the horizontal track the arms slide across)

Anybody have any tips/tricks to get these things rolling down a little better - instead of looking for older, beat up doors.

Thx!