Okay, I'll spill the rest of the info on the tractor now.
I have determined that it is a 1946 H. The loader was indeed built by New Idea, although I cannot remember what they called it. It's on the ID tag for the loader, so I'll have to have a closer look some time. The bucket trip mechanism is much more solid and reliably built than the bucket trip on our M. We actually have a second cable on the M's bucket trip, that we have to pull on in order to keep the bucket from tipping because otherwise it'll just shake itself loose and tip the bucket at the worst possible time...
So after getting it home, the first thing to go was the plastic battery box. Pulled the hood off it and then pulled the distributor apart to get access to the points. They were definitely in need of a good cleaning, and I will probably replace them soon as one of them has a pretty good pit in the surface. Then I went after the carb, I just had to pull the bottom half off as it was pretty clean and there was nothing blocked off in the upper part. I will be buying a rebuild kit and rebuilding the carb soon. Partly because I have 2 leak spots on the bottom of it now due to seals that aren't sealing anymore. I had to make a new gasket for it since the old one tore, and I think my custom one might be better than the one that was on there- it didn't leak a single drop from around that gasket.
So with the points cleaned and carb cleaned, now I needed to figure out a power supply. The battery it had in it was long dead, so dead that the charge would drop almost instantly as soon as I took it off the charger. I ended up stealing a big 12 volt battery out of an old diesel pickup truck we have sitting around that won't start. With the large battery, the engine cranked over easily. I checked spark and had good spark. So I made the first attempt to start it. No luck. I opened the main jet on the carb 2 1/2 turns and tried again- fired right up!
The sound of it with no exhaust pipe at all is crazy, but kinda cool at the same time. It doesn't run perfectly smooth, another reason the carb will get a rebuild soon. Despite how rusty it is the oil pressure gauge even works. After letting it run and warm up for a bit I began testing things. The belt pulley works, the PTO works, the lights all work, and the loader works too! In case something goes wrong with them the tractor came with a set of spare hydraulic cylinders, which is nice. The last thing to test was how it drove, and it actually drove well.
So that's where I'm at with this thing. Far from done with it, gonna rig up a straight pipe for the exhaust, rebuild the carb, and replace the points, as well as make the wiring a little neater. Probably will remove all the lichens growing on it (sorry Kraig and Jim!) and try to clean up the paint underneath.