I've been out caulking my unit, as well. I'm thinking that the yards and yards of linear caulk are to a significant degree, over caulking screws that penetrate the skin,. And I'm thinking that if mfg used neoprene washers (like roofing screws), that all of this caulk wouldn't be necessary. Don't the side panels 'lap' one another, like shingles ? Ideas anyone ?
Amurdock - not my intent to hijack your thread, but to expand on your question.