How to deal with HT bad seals between front/ quarter windows?

On the 67 the rear window has a chrome strip attached to the glass. The seal goes into the chrome strip. Dang near lost the use of both my thumbs trying to get the seal in.

OEM has a molded in top cover. Aftermarket it is glued on, (or should I say was glued on)
Interesting to see DMTs note about fit flocked vs unflocked