I would strongly recommend taking any CS engine completely apart for a good clean prior to its even being turned over. You can also use the opportunity to remove any machining burrs and flashing - there's usually some of that to be seen. Dismatling is best done in a tray or wide dish which will catch any small parts which you may drop during the dismantling process.
While you have it apart, you should stress-relieve the shaft. This is very simple - you place the cleaned shaft in a cold domestic oven which you then heat up to 550 degrees F. Leave it there for 2 hours and then switch the oven off and allow it to cool slowly over the next few hours. After it's cooled to the point where you can handle the shaft, it's done. The shaft will have a blue tint to it after this treatment, but it will be far tougher since the steel will have had internal stresses relieved and the material will be normalized. The CS engines have a tendency to break shafts if this is not done, since the material is over-hardened and is not stress-relieved. By contrast, I have yet to break a CS shaft which was heat-treated in the above manner.
A point to note when taking the shaft out - many of the engines have thin shims behind the front ball race to set the correct end-float in the shaft. Do not lose these when dismantling the engine, and make sure that you re-fit them when re-assembling! You should also ensure that the circlips which retain the wrist pin are in place. (no need to disturb the pin itself) If not, the pin can score the bore. When dismantling, it's always a good idea to mark the cylinder lightly with a Dremel tool so that it can be reassembled in the same position. It's also wise to mark the piston as well for the same reason.
You'll have to drill out the hub of a stock prop to fit the Ollie prop mounting system. Make sure that you re-balance the prop afterwards!
If you do this, you'll end up with a fine-running easy-starting engine that should give good service. I have two of them in models, both of which have served me well. However, be careful of those dealers - they tend to over-charge people for engines like these! If well set up, this is a good $100 engine, although it takes some effort by the owner to get it to that point.