DOOR GLASS CHANNEL FELTS STRUGGLE!

Having trouble with my new kit, part #MN3104 I got from Classic Industries.

MN3104 - 1967-74 A-Body; 1966-70 B-Body Front Door Glass Channel Seals

I tried to to slide the glass down the new channel felt with the new clips, and experienced strong difficulties! It was way to tight, and I ended up ripping up the new felt channel. Before I try the other door, and order another kit, has anyone else experienced the same struggle?

FRUSTRATED!!