Replace the outer-most crankshaft bearings to be safe. At the very least, check their tolerance for excess play. ( I realize it may be too late to check this now.)
An oversized job usually results in more power, so be sure not to let it over-rev! Re-clutch to bring the RPM's back down to spec at wide open throttle. Run the first tank of fuel with some pre-mix oil added, maybe raise the needle one position to be safe (in the carb) and vary your throttle position often during the break-in procedure. At least that's what i did.
Oh, and don't forget to check and bleed your coolant system, get all the air bubbles out that sit in small crevices. When you start the engine the first time, get the front end of the sled up high so the engine sits flat and most of the air bubbles will move out. Good luck!
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