[KobraKarl]

Hi Kasman , Welcome...

Your temp fluctuations are more typical than not......some factors could be....

Wrong stat....or no stat

Engine bored .030 over or more

stock water pump..I would get Edlebrock unit

Ignition timing too advanced

Too lean fuel mix

Puller fans.......stat starting them at 90-95 C..not 100-105 C

water wetter

A little of all of the above

Try a search too ....there are many of us who have sorted this out , and a lot of good ideas are contained in old threads.

Good luck, KK