I finished up some of the first stage of some 12V wiring improvements. I'll post more gory details at some point before too long in the DIY forum.
If you have a Coachmen motorhome, check to see if there's a little DC distribution bus bar system near the positive house battery connection. On mine, it's mounted on a little chassis along with the main house battery fuse (of 175A, I think) and the house/chassis battery isolation relay. This bus bar feeds a few of the self-resetting circuit breakers, which are mounted in a little plastic bracket. This nifty plastic bracket has a somewhat flawed design, in my opinion.
The problem is that the bracket wraps around the load side of the circuit breakers, and insulates the load connections from the base of the stud on the circuit breaker. This means that the full load current has to go through the nut holding the load ring connector onto the circuit breaker stud, rather than directly from the stud to the terminal. In general, nuts and other threaded connections should not be the primary current carrying connections.
I replaced the plastic one with
this nice metal one which works well (the breakers are clamped in very securely). The spacing of the breakers is identical, so the bus bar itself doesn't need modification, but the mounting holes for the holder are spaced further apart which necessitated a new hole in the chassis it mounts onto. The metal bracket does not work with manual reset breakers, as I discovered the one for the power steps initially was.