I removed the Antenna on my 1980 Excella II and put a patch plate over the hole. I believe you may be talking about me. Here
is the thread.
I used Vulkem Sealant and 3/16 pop rivets. I did not use enough rivets and also I did not use the right kind so it leaked again. I put vulkem over the madrel hole of each rivet and then used heavy aluminum tape over that. Learn from my mistakes and use olympic rivets and shave them so they shed water, and space them close like on the windows OR use big pop rivets, cover the hole with vulkem and aluminum tape over that as i finally did, it will be on the roof so no one will see it anyway.