I used the glass specialist that replace windshields to re-glue both my glass and seal. form what I understand they used the same glue for the seal as for the glass. I guess its some sort of polyurethane based glue (not sure if that’s the correct term). my tip would be to ask your local automotive glass service what they would recommend.
regarding the lip. I would say that it’s always best to have the same sized lip around the entire glass (centered glass). but if it differs with a couple of millimeters I really don’t see that this would effect in a way. as long as the seal have enough lip to grip to and be able to stay without glue (as a test) I think you’re safe.
if it differs a lot I guess the outcome will be that the seal doesn’t seal properly in the roof opening once it’s installed.
But if you really want to be on the safe side. take it all to the specialist an have the install both at the same time. I remember that my glass specialist told me that he installed the seal while the glass and frame still hadn’t cured. this gave him enough play in the glass so that the seal “centered” it during the installation.
I’m really sad to here that you cut one to short.. I would have been devastated in that situation since it’s not cheap
haha yes you really have to dig deep in you pocket to purchase parts for these cars.
hope this can be of any help.