Burl, I'd have to think about that for a while.
Orion, I have the flat cover. There are only two screws, top center and bottom center on mine. The top hole might be there in the photo, I can't tell.
I don't know what a Trik-L-Start is, other than it is something you can add to join the batteries together for charging the chassis battery from the coach system. I've read of it on the forum.
I have an idea of something that would use the disconnect relays and a Battery Tender or other maintainer charger. It would be easier if I sketch it.