I made my own harness. It was pretty easy and a fun job. When unsure of wire size, lean towards the heavier side. You can never go wrong with larger wire, its just a little harder to work with. With 6 volt battery cables, go as big as you can 2/0 or even 3/0. Use a lot of heavy well grounded ground straps and you should have any problems. Add a few extra wires for under the dash and a few for under the hood for extras options that may come along in the future, Radio, A/C, electronic ignition...
Joe
