Hey John,
Most of the guys I know with the 7.3 have very little trouble with them. Most Cummins guys I know say(including me) "If they didn't have the Cummins I'd be a Ford 7.3 owner". I think a lot of the "sought after" is the 2000-2001 models as I think these models had the least amount of complaints, reported issues of any.
It's one of those things that makes you wonder. Ford said it dropped the 7.3 due to the expense of re-engineering it to meet EPA standards. So they introduced the 6.0 and 6.4L catastrophe and I often wonder how much money they spent on those boat anchors compared to upgrading the 7.3.
I think you found a winner right there, 84k it's like brand new still! It's not a pitch line, lots of guys looking for those trucks like you said the other day about the emissions stuff not being there plus they were ultra dependable.