Does anyone know if the forward vertical felt channel that lays in the

rear of the wing window frame can be replaced without removing the door
panel ?  The forward portion of the roll-up glass travels up and down
this piece of weatherstripping and after replacing the other two pieces,
I am wondering if this section is as easy. It looks like it is easily
pulled out though I am not sure inserting the new one would be simple
with the panel on.

Any ideas based on experience are appreciated  !!

-john