Teri, you can sand the lip to thin it out where you need to get your seal to fit.
I've reworked the lip on mine, adding & deleting material where needed for a more consistent gap. (Using a cardboard template cut for min / max gap for a quick check.)
Parchment paper over a board acted as a form for adding material. Grayish material is the extended / squared up lip at the middle front. (I use Everglass Fiberglass Reinforced Filler by Evercoat -- easy to work & shape for filling voids, cracks, holes or adding material.)
The roof on my Campster
undulates with high points at the structural cabinet verticals. Blue tape indicates an area marked to remove material with a Dremel Tool & sanding bit.
Currently I'm sanding & prepping for paint
on the top before installing the slightly larger black bulb seal pictured with the original.
I'm also adding (and removing) wood where needed to the upper frame and have added a foam strip to the lower frame to create a dust seal there. This buildup is also providing a needed increase in tension on one of the hold down latches. (BTW these are same as Jeep hood latches, with many sources at a modest cost on EBAY.)
Hoping these details & attached photos may be of use to another Campster
owner. The pop-top is clever, simple, and effective, but mine requires custom fitting for a good seal. With the wood cabinetry being a structural element, keeping it dry is a primary need.
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