I could not find a wiring diagram or any brochures etc for a 2016 Navion, so I looked at the 2015. I did not see a Trik-L-Start, but I did find your solenoid and battery DC relay and they are with a circuit breaker panel. I wish I could tell you where that is, but if you dig into the diagrams they will eventually lead you there.
Luna was born in 2005 and is a Winnebago Journey 34H w/ CAT C7 350
Camper Ken, there are two issues with not disconnecting the batteries. First there is a chance of your wrench touching something that is grounded and causing some physical damage. Second there is a lot of statistic generated when you loosen connectors that have power on them which is not good for the electronic devices.
Grant & Pat
2014 Adventurer 35P
2012 Jeep Wrangler Rubicon