http://www.skycraftsurplus.com/14awgdlo2kvblack-1-1-1-1-1-1.aspxSixty feet minimum purchase.
Use the "excess" to correct the laughingstock wiring from the alternator to the charge divider solenoid, then from there to the house batteries. Spud a length from batteries to chassis negative.
This takes care of ALL your OEM garbage grade wiring. You won't believe how much FASTER your batteries will charge from the converter OR the alternator.
WAIT! Someone out there is already screaming "Too big of wire between alternator and chassis and house batteries!" Please give me a few years to go back and "correct" the hundred plus rigs I have successfully done this on.