Another option, just in case. On ours, I removed the Marinco power inlet and removed the wires there. I fished the cable back into the basement and installed the unit there, then installed a new run of #6 cable from the PD unit to the Marinco inlet. This way I didn't have to fool with the breaker box at all. Not sure where the inlet is on the Sabre's though.
John and Rebecca Dickson
Emma-7 / Little John-5 / Iva-1
Full Timing Again, Rev B
2013 Ford F-350 Lariat CC LB PSD
2015 SOB TT - With OC's Awning Poles (#8)
At least in Heaven, RVs will be perfect, and I won't have to keep fixing them.