More good info, thank you!
I looked under the truck today and the spare tire is the original Goodyear 235/85r16 so I guess that solidifies my tire size choice. The spare has never been used so replacing it would be wasteful IMO.
I also located a new factory steering box/frame brace so that is on the way.
Upon close inspection the transmission lines under the hood seem to be a little wet in spots so I will keep an eye on those. Hopefully I can tighten the clamps to get by. If not I'll pull them off and have the local Parker dealer make a new set.
Here is the interior: