[vettestr]

I have a generic sketch that might help. This will allow you to turn fans on with toggle sw. whenever key is on or will turn on automatic if engine reaches temp sw point and key is on. You will need a 20 to 30 amp relay for about 10 bucks and a normally open temp sw you bolt into block/water passage (mount near rear of block as it is higher there) at what ever temp you select. I use 170 degree and cost about 25 bucks in Jegs. This diagram is suppling B+ all the time key is on and using Neg. or ground to turn fans on via relay through temp sw. or you can turn on anytime with toggle. Be sure to use a fuse at 30 % above fan amp run rating and place relay signal gated by ignition sw.