To30 questions...new purchase. Overheating and other issues

newbie here. Don't judge. First tractor. Im unclear on the year. Where can I find this? I have a picture posted of plate on engine but no other plates available I see anywhere. Anywho. I changed the oil before. Water present. And I ran her a few mins but overheated...today heres what happened. Yes I tested low compression on two cylinders. Absolutely 0 psi. Others were solid.

I wss hoping my low compression was just a stuck valve. Popped the valve covers and it wss rusty. Cleaned what I could. Dumped atf. Drained oil several minutes later...large amount of water in oil "again" 2nd oil change since I've had it. She over heats big time. I tore it apart hoping it was thermostat. But apparently it's been removed...so I filled with water. Operated wster pump by hand. No change in flow on open end of water pump. So the impeller is probably rusted crumbs. So either wster pump failed and they ran it stupid hot to make head gasket failure. Or its just head gasket failure.
I ran 15w40 shell Rotella.

Also is the trans and hydraulic filler by the gear shifter? Or different area? I didnt look everywhere. I popped this open and bone dry. So I filled with whatever I had laying around. Just to get something inside while she shits. Im a truck driver so I'm not around much. Fyi I'm in Texas so now worried about cold weather and thick oil.

Sounds like a head gasket (at least) to me. These blocks have a reputation for cracking between the cylinders which allows coolant into the oil, but your zero compression on two (adjacent?) cylinders is very likely the head gasket which also can allow coolant into the oil. Time to open a can of worms and pull the head IMO. Get the I&T shop manual (available from this site) and follow the step by step instructions for disassembly and reassembly. I'd probably drop the pan also and inspect the block for cracks between the cylinders on the lower end. There may be no place to stop...

There should be a plate riveted to the dash with a serial number which tells a lot about the machine. They do go missing. A TO-30 will have a screened air intake on the right side of the dash and a Z129 engine.