The JD 6068 is a great engine: heavy block, lots of bearing area, hp is reasonable for displacement.
But how it was used and maintained over the past 9,700 hours is all important.
Does it start up easily from stone cold? Any blue smoke in exhaust (oil burning)? Black smoke (overloaded)? Does it overheat at wot? Will it get up to rated rpm at wot (if not it probably is over propped which could take its toll after 9,700 hours).
Those are the questions to ask. You probably should get an engine survey if any of the above don't look good.
David