Help, window regulator problem.

Right could really do with some help on this one before i go completely bonkers.
Picked up a new NSF reg at the weekend for my 300tdi. Now the motor is the same as the one i removed, also the arms are the same length.
Only difference i've noticed is the plastic bits on the end of the arms, old ones were round and the new ones are rectangular.
Managed to get the new one bolted up to the window and door, powered up and began testing.
Motor works, but when raising the glass it gets about 6" from the top and slows right down to a crawl whilst pushing out the inner skin of the door.
On closer inspection the plastic slider nearest the dash attached to the window is hitting the bolt furthest right on the glass mount, trying to carry on past it.
Anyone got an idea as too why this is happening?

I have pictures of the regs but can't post them till i get home. Was hopeing i'm missing something and it would be pointed out to be before i give up and go home lol.

Cheers in advance to anyone how can help.

Chris.

Without looking at the installed regulator it's hard to say other then its been fitted incorrectly or you have the wrong regulator.

Nope lol. Managed to figure it out in the end. The plate thats attached to the glass itself had slid along the glass about 2" meaning that the plastic sliders couldn't move across as far as they should and were fowling on the bolt at the end.
Managed to prize it off and re-position it and got the winodw working.
Still a bit slow when it gets to the middle but who cares, I have a working passenger window for the first time since i've owned the truck. :lol: