I just had to replace a vent in my TT due to a broken frame.
Once I cleared the screw heads and removed the screws I used a wide plastic putty knife to push between the roof and the vent frame. Once I got it loose enough to grab a flange with my fingers I pulled up and the vent came free.
Then I used the same plastic knife to carefully work the old Dicor and the butyl tape away from the rubber roof. I also utilized a small plastic kitchen scraper for the finer bits.
Changing the vent was about a 15 minute job. Scraping all the old goo and schmoo off took me about 2 hours.
Have patience and know it will take a while and you'll be fine! Do be careful not to puncture or tear the rubber.
2007 GMC 3500 dually ext. cab 4X4 LBZ Dmax/Allison - 2007 Pacific Coachworks Tango 306RLSS
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