Hope you have a good and safe trip. I have a metal building I erected with some buddies a couple years ago to store our first rv and installed a 30amp service as well. Just installed a Maxxair Deluxe in the bathroom today, but I'm still waiting on my caulk to arrive first of next week to complete that project. From what I can tell, the roof on our 174BH is called a Dicor DiflexII membrane. I'm using the two part Dicor Ultrasealant Primer and Ultrasealant caulk to seal in the fan assembly. I tried using professional grade urethane caulk and a good grade acrylic caulk on the membrane I had in the shop but no luck with sticking appropriately to the membrane. I cut off a piece of the membrane that was hanging down in the vent opening for a test piece with the caulks I had on hand. I even tried wiping down a portion of the test piece with acetone and then applying the urethane caulk but no go; the caulk came off to easy for my liking. Just wondering if your 26BH has the Dicor DiflexII membrane as well. If you don't know, you can e-mail Jayco support and give them your serial# (which evidently is the last eight digits of your vin#) and they can tell you what roof you have. Jayco has been installing Alpha Systems roofs and Dicor brands over the past few years. You need to which roof you have before you buy or do maintenance on your roof.