I made several 'taps' into the 2/0 cable to syphon a little juice off to my DC-DC convertor and to run the voltmeters. The Curtis 900 battery state-of-charge likes to be on all the time so I spliced that in pre-contactor switch, and the regular instantaneous voltage gauge wires I ran in AFTER the contactor so that I would have visual verification when the system is powered up with the key on.