My 73hatchback/ 2 door: I don't have the vent you do in the front but the U channel, the part the glass slides into to seal when rolled up, also goes down inside of the door in the front track is not hard to pull out. it does extend down into the door cavity, so you may want to remove the door inner panel to facilitate removal and especially install of the new one.
it`s ocean city, md. i`m only 3 1/2 hours away in pa., but i don`t want to chance it,,,,,,, like a plastic see-thru gas filter, 2 inches from the fuel pump,,, no thanks, header rub on steering box, big exhaust rattle, maybe i`m a little anal, but, no, piece of mind is priceless. and i know something can go wrong out-of-the-blue, but i`m sure, like most of you guys, ya try to handle everything for safety`s sake.,,,,, thanks to you guys for my help! can`t wait to post pics for ya. it`s exactly one year since "margie" was totalled.