Hi Roverdude45,
I appreciate what Bruce has said in the above post and thus has pointed you in the right direction regarding the said component but I note that Price is an issue and the thought of purchasing a replacement engine is on your mind, thus I have come up with the following solution.
No need to worry about that engine shaft as I feel it will be fine. All I would do is rub it fully with a fine grade emery to remove any burs. I know that the damage from the set screws looks bad but it's not that critical because the parts of the shaft that need to be absolutely parallel are just before the screw location and also at the end of the shaft. Now as the mating parts are steel and die cast, it will always be the die cast that wears away, not the steel. The worn groove left by the screws are only going to have the screws bite into it again to stop any movement. Hope that explains it for you, also if you thinking of totally eliminating the issue, a new Chonda engine at around $129 delivered would be the obvious choice.
Now,
You'll have to purchase another clutch half, Thrust Bearing that's internally damaged, Key steel and also buy a new cork lining along with the glue required to do the job. Oh and BTW don't forget to purchase a new black plastic clutch thrust pad. This will ensure a square push on the clutch cone.
Re-use your current set screws from the previous clutch thus saving on costs of replacements. The screws will be fine on the PTO shaft as long as they are done up nice and tight again, thus with the fitment of a new clutch body all parts will fit together rather snug and perfectly aligned.
Once you've done that I'll walk you through the re-installation of the engine.
And, just a quick check on the square catcher rubber blocks in case you are missing either one. Always pays to purchase as much as you need in one go so as to save on postage costs.
Cheers,
BB
PS. Yes those rails are A OK, very lucky indeed I must say considering the state of your clutch.
