if the temp rises "unnormally" fast could be a low coolant condition, or a poorly bleeded CS, or a stuck thermostat,
If I where you I wil definetelly (in a rad shop) clean and decalcify the rad, put a new Water P, new thermostat, check for old hoses (internally broken and thus making some kinda flap) and (sorry) new cluthc... while at it, if you want some "FREE" Hp, or "free" MPG why not get rid of the engine driven fan and put a electric motor driven system from summit racing, my brothers Chev P-up 454 improved T=R=E=M=E=N=D=O=U=S=L=Y (sorry, spelling?) with the mod.
also if the engine dont use aluminium (I supose iron heads) you can get away w/ the "green" coolant.
all parts readily available @ pep boys or simmilar, OK maybe the clutch not but a Hi perf cluch will definetelly be better cheapper (least expensive) in summit than OEM!
I have a date with eternity, AND I DONT WANT TO BE LATE!