Replace Rigid Division Bar & Triangular Vent Seal

[74Corvette]

Hi there I am looking to replace the division bars on a 71 GMC. I have the replacement rigid, felt lined, stainless steel replacements. I have read basically everything I can find related to this on this site and I am not quite sure of a couple things. Can I change these in the installed door or do I have to remove the vent window frame, rollup window etc. If I can replace without removal, is it just as simple as it sounds. Drill out rivets, pullout old bar and replace with new one. I have read that I can even use normal pop rivets with a slight modification to the rivet tool to fit inside the channel.

I also want to replace the vent rubber seal, (the triangular one), I have read many posts on this but most info seems to be on changing the vertical riveted seal. Can I change this seal without complete removal of the vent window or do I need to follow the steps outlined in the FAQ section. Thanks, any help would be appreciated.

[74Corvette]

Well did some disassembly today and figured out that these parts can't be change without the vent window frame removal. If it is possible it is beyond my skill set. Anyway, pulled the vent windows and replaced all seals and division bars by following the steps outlined in the FAQ. Very nice to have proper seals again!