Vic, which brand/model of roof vent did you get?
- The Trillium
4500 roof is raised up around the roof vent opening area.
- The replacement roof vents that I have been installing (14" Ventline and Hengs) have a metal base that extends down into the opening an inch or so. This results in a good fit that is very close to the ceiling.
I find that plastic trim ring (inserted from inside the camper) needs to be cut down/shortened to one inch or so.