So I executed a successful operation, gluing a brand new Snyder JR1 to a Kokatat Trinity Dry Shorty. Jim did an excellent job on the skirt, it installs easier than my original Mountain Surf and is almost as fast as a standard cockpit. It's the driest setup I've ever had in any boat. Beyond amazing.
While perfect for the Upper Gauley or other action filled downriver runs, it traps enough air to be unsuitable for sinking oriented destinations. Others mentioned being able to suck air out of the top, even the boat, which was motivation for performing the operation in the first place. When I suck it out, it comes back pretty quick. It's possible the new fabric will lose stiffness eventually and respond better to sucking.
I intend to install a drysuit exhaust valve and found this handy youtube video comparing the two major brands.
https://www.youtube.com/watch?v=j2_wIvTe1UQAnyone with experience with these scuba exhaust thingys? I think my coming footage will show other squirters with the billowing hunchback bulge of air and bet others may benefit from a well placed exhaust valve in their drytops.