Check neutral safety switch on trans
It is on left side of trans I believe.
It will have two wires on it one from the key switch other to starter
The wire goes to it and from it to starter if in neutral the voltage will go thru to other wire then to starter
It is a safety switch so it doesn't start in gear

No power to sense wire on starter. Have power at key switch going out. Guessing there is a safety switch in between that has failed.

You will have a batt wire, a starter wire an accessory wire and ign on switch
As far as cyl you can only replace the wiper seal the cyl has to be cut open and resealed then welded back as far as the valve it is mostly o rings , buying a cyl is 1100.00-1500.00 it is much more economical to have rebuilt at a hose - hyd Shop I will look for wiring diagram to see if I can find one I am a retired technician from Clark dealership
And may have some info on wiring what is the issue you are having ?

It's pretty basic wiring for these. 3 or 4 wires needed. 1 battery positive. Goes to battery on key switch. 2. Start. Wire leading from switch to and or solenoids. If you have 1 or 2. 3 is an ignition wire to distributor. IGN on back of switch. Back in these days, they put inline fuses wherever they liked to. Buss fuse holders. 4 is possibly miscellaneous to gauges , again most likely through the inline fuses.
The steer cylinder is most likely obsolete. A seal kit possibly available through TVH. And or good cylinder shop can also match them up or make you a new rod if needed. Is the lift worth it?