1958 MF85 owner needs advice

[Blackriver]

Hello all, I'm Mike, from NE Arkansas. I have inherited a 1958 Massey Ferguson MF 85 gas engine tractor that belonged to my dad, who passed away last February. He let the tractor sit outside for 30 years and wouldn't let anyone touch it to try and keep it from ruining. Last winter after he passed, I anticipated that the engine would be seized, and I took out the plugs and poured some ATF in the cylinders. Yesterday I finally got around to taking a look at it. I removed the plugs and starter and used a prybar on the ring gear, the engine turns over effortlessly! I drained out the old gas and removed the gas tank, it doesn't look too bad inside. I removed the tappet cover and the valves, tappets and push rods seem to all move ok. I could not find any stuck valves. There doesn't seem to be any water in the oil. But of course, a tractor can't sit outside that long without some issues coming up. I'm a tractor newbie so could use some help dealing with a few issues.

1. I discovered the shifter lever is stuck in neutral, along with the small lever next to it (is it for the PTO?). I removed the plate that holds both levers and discovered quite a bit of rust underneath, shift lever won't move, obviously water got in around the cracked boots. This morning I drained the transmission and about a gallon of water came out before the trans fluid started draining out. Bad news I'm afraid...I haven't inspected the transmission thoroughly yet as it started raining and I had to quit. I sprayed PB blaster on the gear selectors before replacing the cover. Looking into the transmission from above by removing the plate near the seat, everything looks ok, but I suspect it won't look so good from underneath. Any ideas how to free the gear selectors?

2. The steering gears directly underneath the steering wheels are seized solid. I popped off the steering wheel with a puller and removed the gear housing underneath. I guess this part can be replaced? Or how to free it?

3. The lever next to the steering wheel, is that the throttle lever? It is seized too.

I know there will be more issues, and I plan to deal with each one at a time and be careful and slow, these are just the things that were immediately obvious. At least the engine isn't seized, but I'll bet new rings will be needed. I sure would love to hear dad's Massey run again. I plan on ordering a service manual before I tackle anything major, but would sure love to hear what you guys would do if you were in my place. Thanks!

Here's a pic from earlier in summer before I pulled it out of the weeds:

 

[Dieseltech]

The small lever is the Hi-start-low transmission range lever, long one is 1,2,3,4, and Reverse. The gearbox under the steering wheel may be easier to replace than fix it. The throttle lever under the steering wheel most likely is rusted at the friction disc above the battery, I would look there first.

 

[Eyecatcher]

Don't try to turn the steering wheel until you have hydraulic pressure. If you do, something else will brake. The PTO & power steering have their own pump.

 

[Navasot]

Not sure how to clean up everything without ruining any seals but soaking it in diesel may do the trick.