Neg connects to battery and engine block. Power connects to battery and pos terminal on starter solinoid.
I had to shape up the terminal a bit where it connected to the block but full surface contact was there. Zoom in the pic of the starter installed, you can see the block side of the neg.
I took the stock harness totally out and disassembled it to see how to rebuild. I also put new terminal lugs on my battery.
Basically am adding a 2nd batt and wanted all the power runs to be new.