I believe this plane has been listed in the club classifieds, and may still be. The classifieds are currently not working, but I seem to remember that the ad there listed the hours as "STOH" instead of "since overhaul" as the seller has put in his ebay ads. Further, when this plane was listed on ebay in December as item number 4597616209, one of the seller's answers said, among other things, "The overhaul was an extensive top...."
I was interested in this plane for awhile, thinking that the 607.2 hours were SMOH, but personally lost interest when I came to the opinion there hadn't been a major in almost 2600 hours.