The steering wheel should come off. Put the nut on it, engaging several threads (so the shaft almost comes flush with the top but not quite). Then use a 3 or 4 inch bolt with a large heavy washer on it, slide that down into the steering column. Now, apply upwards force to the wheel while tapping the bolt head (driving the steering center shaft downward). A few sharp whacks should knock it loose. (This has worked for me on all my tractors except the 72. That devilish machine refused to budge! So this method is no guarantee.)
Your mule drive does look bent, but the pulleys are "tilted" on QL tractors to accommodate the off center drive pulley on the 44A and 50A mower decks. The mounting frame of the mule drive should be square, though.
The loose drive collar on the hydro unit is typical. Knock that pin out, check the hole in the input shaft. If it's badly wallowed out, you might have to repair it, but generally they don't get that bad, and you can probably run it as is. Put in a new spirol pin when you reassemble. Most of mine have a little play in them.
__________________
|