This the tool to make an access panel. If you install the heat blankets, some will have a light that will install in your Rv when they're on. Here's a video on how to install tank heaters, but you can google other videos also.
You have to make your own access and they you could seal it with Gorilla tape, or they sell specific tape for the under the rv cover.
Mark & Susan
'13 Cruiser Patriot 335SS - '13 Ford F150 SCREW - PullRite Superslide - Roadmaster Active Suspension Member - "Northeast Adventures RV Rally Group" & "Mason-Dixon Bunch"
If you do cut access holes or cut part of it out, splurge and get the proper RV tape from a dealer. Well worth it and works great. I bought some when I had to replace part of my underbelly from the front axle back. Still holding after 3 years. And the replacement underbelly is way better than factory.
2013 Zinger ZT260BH towed by a 2013 Silverado Z71 1500 CC 5.3L