Thanks for all the info. I received my tractor and engine service manuals today so that will help a lot.
When my valves are open and I try to move them side to side they have quite a bit of play. they may need replaced. I pryed up on the bottom of the bushing with a screwdriver and removed the clip with plyers but the valve, spring and bushing assembly doesn't want to come out. Is this a common problem? If the bushing is stuck and needs to be driven out is it possible to remove the cam and then pull the lifters out of the middle, compress the spring and remvoe the keepers, remove valve and spring and then be able to drive it out?

I don't believe the cam can be removed without first removing the valves and lifters, the bearing journal on the rear of the camshaft will contact the lifter before it will come out far enough to be removed. I have had trouble getting the valve bushings out of these motors before, but with a little careful prying, penetrating oil, and patience they have come out. It just takes a very little carbon or rust buildup to make them stick in the bores.

I finally was able to get the valve, spring and guide assembly's out but I did remove the camshaft first. I took four clothes pins apart and turned the engine until the cam lobe had the valve open, I then installed two clothes pins unde the valve heads I did it to other three valves and then was able to remove the cam. (I know clothes pins but it worked ) After the cam was removed you could pull out the two exhuast lifters from the inside. I used a c clamp to hold the valve and then removed the keepers. Once the valve and spring were removed you can take a brass punch and tap the guide out buy going from the outside toward the inside, I think the reason they don't want to come out as an assembly is because the groove that holds the c clip gets hung up trying to go through the bore. I'm going to clean the bores up with a brass bore brush. I think I'm going to replace all the guides and probably new valves but I'm not sure what I'm going to do with seats yet, they are held in with the valve sring and c clip. If I have the seats ground I will have to put the guides in with the c clip and then have the spring on the inside with some type of spacer to put pressure on it to hold the guide in?

Hi TomP-TX,
from memory the cutter mandrel is the same or very similar to the Side Valve Ford V8 mandrel. But I stand to be corrected.
Cheers,
Eddie B.