What to put under T-top plates

[flbuick]

I am reinstalling my Ttop plates to the body and wonder what people are using as a sealant to the body. It looks like GM didnt use anything and then we get rust. I was thinking foam filled butyl tape which is thin foam with sticky butyl compound on each side. Or maybe black silicone. Just want to keep water out and keep the metal from rubbing together and causing rust.
Any other ideas?

 

[blackazz]

Sikaflex works great in the construction field.I also have a cc1 TR thinking of the same thing.