Starter wire to relay-HELP

[sixpack_sid]

I am hooking up the engine harness for my 440 eng in my 68 Charger. I bought a Pos. battery cable with a lead. Can I extend that lead to hook into the starter relay on the firewall? What gauge should it be? The other little wire that comes off the starter, I'm going to run to the S on the starter relay. Is that correct?
Thanks!
Sid

[nascarxx29]

The brown wire thats the usual color goes to the small terminal on starter.And screws on the starter relay.If you using the original mopar type relay.The extra wire from battery cable bolts onto the starter relay 10  to 12 gauge I believe
http://www.mymopar.com/downloads/1968/68ChargerA.JPG
http://www.mymopar.com/downloads/1968/68ChargerB.JPG