Not sure. When I pulled a window out one time, I doubled and tripled up on strips of tape in areas that would fit in the valleys of the aluminum. As I recall, I did one strip all the way around the window, and then put the pieces on the clean trailer surface to level it out, then put the window up there.
2007 T-286SR Cherry/Granola, #6236, original owner, current mileage: 9467.8 (as of 5/26/19)
1997 T-2653 Blue Denim, #5471
1979 12 1/2' MC, Beige & Avocado, #4639
Past Sunlines: '97 T-2653 #5089, '94 T-2251, '86 T-1550, '94 T-2363, '98 T-270SR