Originally Posted by Will Parish
The existing hole is about 1 1/2" already and I made it larger just using a razor blade.
The existing hole is covered up with a metal plate and lots of caulking.
The extended shaft that goes into the interior and I had very little to cut.
Here is my finished MOD.
The old screw holes I cover with Eternabond which adhered very well after a good cleaning of the surface. I have had it on for over a year now and no leaks.
Here is the existing hole and the one that I made. As long as you read the instructions and seal correctly you will have no issues.