Hello All - hopeful future Gen 3 Coupe builder/owner here. Been following the build threads for a little while, and done a little searching, but haven't come across anything related to the following:

1) It looks like some builders put silicone sealant between the steel structural members and the aluminum panels. For those that don't, how do you seal up the drilled (or drilled & tapped) holes where you put rivets/screws in so as to prevent rust streaking when you wash the undercarriage?

2) Has anyone put any type of bumper at the rear and/or front of their cars to help prevent minor collision/incidental parking lot damage? I've seen how the older Corvette fiberglass bodies can "split" during an impact. Do the coupe bodies do the same? I'm thinking that if I do build a car, I'm going to drive it regularly, and I'd like to mitigate the "minor" damage risk as much as is practical.

Thanks in advance!

Matt