Vent window weatherstripping

[afcamaro]

I am in need of some ideas on my vent windows. I am replacing the weatherstripping right now and cant seem to get the weatherstripping tightly into the channel of the vent window, mostly the little corner of the vent window itself. I can do the rivets and everything and actually find that pretty easy but getting this rubber to seat is almost impossible! I have tried soap and that didn't help and have messed with these things for hours and tugging on them. Is there any suggestions or anyone I can send them to and pay to have done? Thanks