Need help on divider bar seal install

[66farmer]

I need to install the divider bar and new window felt to the vent window.
I read Allen,s write up but he didn,t go into deepth about the install of the felt.
Do I need to drill through the bottom of the felt seal for the rivits if so what is the best way. the felt seal has a steel ribbed back bone it,s hard to drill through.

If someone that has done this could give me some pointers I would appreciate

[Alan's Classic]

If I understand the question your question is about the long fuzzy weatherstrip (glass run)? I didn't rivet mine. It was a snug fit and the one I removed wasn't riveted either.

I didn't have to drill any of the weatherstrips out when I installed them. Everything lined up pretty good.

[66farmer]

The way I,m looking at it if I don,t the rivits will hold the seal from going in all the way. If you look at the above picture of the lower end of the channel, if I diddn,t cut those square holes the rivet ends would of held the seal from seating all the way in the channel.
My old one has holes in the felt so the rivits wouldn,t be in the way of the felt seating in the channel all the way.