I'm in the middle of installing an American Autowire classic update harness in my '64 GTO. The instructions say to seal the outside of the firewall plugs with silicone. I think this is a really bad plan. Hard to execute and ensure that all terminals get sealed. Also hard to do without making a messy nightmare. I read a few paces where people suggest sealing the plugs with dielectric grease. I like this plan a lot more. Looking for experience or thoughts on this.
https://www.americanautowire.com/sho...iac-gto-510188