This is part 2 of my battery box mod...
In part 1 I designed and installed a battery box extension to house bigger batteries and a shunt for the battery monitor. You can find the details here. The plans are available on the classifieds.
I have now completed part 2 which is the shunt install, wiring and the Trimetric monitor. Photo of the battery box with shunt and wires is attached. We have a 28' International, and the monitor fit very nicely right above the propane sensor below the couch cushion. It was relatively easy to route the wires alongside the current battery wire bundle, go up through the floor in the same hole, and then under the couch with no new drilling of holes except to mount the monitor. I tried to fish the wire through the current cable protector but was not able, so I plan to add wire protection.