Fan clutch ?

[Hudsonaj36]

Hi first post here,

I have a 68 gmc c15 that was original a 6 cylinder but at some point has been swapped to a 350 that I think is a 70's Gen 1 with a short water pump. It currently has a flex fan and a shroud but I would like to put a fan with a clutch on it. Right now it doesn't overheat but in turn it fluctuates temp from 150 to 190 depending on what I'm doing. My thought is a fan with a clutch will help stabilize the temp.

So will any fan and clutch do or are they year specific? Or does anybody have a recommendation? I was thinking about running down to pick and pull and yanking one from a 350 but don't want to get the wrong one.

Thanks