Yes, the roof gutter screw cover and the 4 corners will accept a 1" wide vinyl insert.
The entry doors and the cargo doors are going to be a bugger trying to get 1" wide into that space.
3/4" wide can be a challenge too pending the brand of vinyl insert. Some brands are thicker than others and the thinner goes around the corner easier.
Gently warming the vinyl can help in some cases. Too much heat is no good as the strip will stretch and then shrink faster causing issues. But gentle heat can make to bend around the corner easier. Again, this is brand specific as some the thicker ones just won't really work well.
The day temps also make a difference. Being 50F out and cool works different than being 80F out all day long.
I do not know a good trick on how to get 1" wide to go around the corners of the cargo doors and not wrinkle. 3/4" is hard enough. The cargo doors are even worse then the main entry doors as the radius is smaller.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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