I recently purchased a 1968 Ranchero Fairlane 500 GT and would like to know if there is a Mustang II suspension kit available or can it even be installed since this is a unibody vehicle? This would improve the handling and get rid of the shock towers, etc. Any help would be greatly appreciated.

 

Why?
My first answer is why. your engine bay is way big enough for most Ford
engines, except maybe the 385 series.
I'd work with what I have and not open a can of worms, unless you are
just wanting to do it. all new ball joints, new springs, and shocks.
beef up the leaf springs and new shocks. If the steering seems loose
you can have the unit rebuilt of replace it...
good luck