Nice!
AC made a crap load of WD’s and WD45’s they are still doing a lot of farm work. A lot of organic farm startups are snapping up the old AC equipment.
One thing to watch is the frost ( sand casting) plugs in the head. Not keeping fresh antifreeze in the block will eventually drive the coolant pH down and start corroding the plugs in the head. When they go, the coolant dumps right into crank case leading to a milkshake mess and mucho badness. That’s what happened to my 45.
Before you put the working motor back in, a seal kit is super cheap and worth it. The oil pan and rear main is a bit tricky but doable. Personally I’d pull the head and check it, and install new plugs. Really not necessary to deck the block or head unless it’s really bad.
At least pull the valve cover and make sure the ends of the rocker arm tubes are still plugged. The AC motors of the day used bypass oiling and if the rocker arm tubes aren’t plugged, oil won’t make it to the rocker arms.
These tractors were made to be OH by the farmer under a tree. That’s what’s so awesome about them.