Originally Posted by Aussieguy
just in case you missed it
leave the main negative cable connected at the frame.
the battery end of that negative cable goes to the shunt
The OTHER SIDE of the shunt gets connected to the negative battery post
use same sized negative cable that connects to the frame.
There will also be a small red wire (positive) on the shunt
it needs to be connected to the battery positive (or positive bus bar).
Did you miss the part where he's also hooking up an inverter?
Also, LiFePo4 batteries will often draw max current from the converter/charger which often causes voltage drop issues on the original ground wire installed at factory. Ideally, when upgrading to LiFePo4 batteries the wire from converter to battery should be upgraded. Also the ground wires at converter/power center and at battery.
Of course you'll learn this when you upgrade your own batteries to LiFePo4.