1928 model a window regulator?

i have this 28 a sedan that I am putting together and the glass and channel hit the backside of the aftermarket regulator are there different kinds of regulators. this came from vintique the door is straight as an arrow on the inner. window channels stock it has been chopped 4 inches but like I say everything works till you put the regulator in then it gets stuck. anybody run into this before I throw the regulator through the wall. thanks drew oh yeah both sides are the same and the rears work perfect

 

Its probably the rivet on the regulator catching the window channel. the new regulators have a rivet that sticks out too far. 1/8th more than the originals. I had the same problem. I couldnt see down inside the door to catch what was binding. Finally spotted it after an hour of playing with it. I cut a 1 inch notch out of the inner edge of the window channel so it doesnt get caught on the regulator rivet. I dont think you should shave the rivet down for obvious reasons.