Couldn't help but notice your moniker, 641Workmaster. My SIL just bought one with a 5' rotary cutter to clear some property. Seems to be a good tractor with a few problems we'll work through. Seems alittle on the fast side in 1st and reverse tho.
definitely a lot more tractor than my old TE20 Fergie.

re. your overheat problem. You may have dodged the bullet. The water pump swap is definitely called for. I run a 160 thermostat in my old 216 and it never gets above the "8" in 180 on the gauge. I tried a 180 to see if it would do away with cold weather condensation (it didn't) and it casued the engine to run alittle past the "0". So I put the 160 back in.
You may consider a 160 if you aren't running one.

Dave