Here is what I did for mine (I used the Painless Wiring starter relay kit):
- http://www.4crawler.com/4x4/CheapTricks/Starter.shtml#OtherOptions

Works well, only need to splice into the wire at the starter solenoid, I used a male-female connector there so I could use the starter normally or with the relay just by swapping connections.

r.c.brown@ieee.org
TruckEditor@tlca.org
Project: 4Crawler
4Crawler OffRoad - 4x4Wire discount code