saw interest in electric fans,this is a copy of an e-mail to a bud on a recent retrofit to my '99 gmc 4x4 5.3L
fan is off a '01 crown vic police car 19" fan replaces gms 18" stock one. bosh 75 amp main relay inline maxi fuse holder 50amp fuse. fan leaves 3/4" on each slide, cut a dog house gasket off an '01 ford van .filled the gap and sealed it up real nice. mounted wiht strips of 10ga. steel using factory mounts, shrink wrapped the lowers where they slide in the radiator. a fan is $152 at McMahon ford it has a low speed brush but i am running high only. used a 160 dregree switch. it closed at 205 wiht it tied to the upper hose . sanded off a head bolt and super glued it. so far so good. fan fan switch closes at 183 degrees -perfect.