Bingo. That's the best way to do it. Just be sure to mount the relay out of the way and somewhere where it won't get wet. My buddy found out what happens when you leave the relay just hanging down by the frame. :lol3:Get a 30 amp relay from a local parts store. It has 4 prongs to connect to.
1. Ground...goes to battery ground
2. power...goes to battery power.
3. Accessory....goes to Holley power wire
4. Switch...goes to stock lp power wire, this wire is usually red wire at stock lp.
Don't ground the holley to the truck frame, Hook the holley ground to battery negative.