not a mopar but...

figured this might be the best place for this

so, i bought a plow truck a while ago, and it has a fiberglass top on it
i picked up a second top to make a dedicated "summer top" with a sunroof and open sides

i came across some pictures online, and they are exactly what i want to do
i figured id ask you guys to help me reverse engineer this thing

i should be able to get the cover and the sides made at any upholstery shop, right?

and the snaps to mount to the top itself, i can just buy online, i figured

now, looking at these pics, it looks like the guy added a ridge around the hole in the top, presumably to keep the water out, any suggestions on how to do that?