What might make the deal worthwhile is if you are able to do the removal
of the old engine and installation
of the new engine yourself. Unless the engine are exact duplicates of each other, there are a lot of variables and lots of "thinking how" time involved in getting the new engine to work with the old engines wires, cables
, hoses, filters, etc., etc. That is why the labor cost seems high.
As Seahunter says: "A easier question to guesstimate would be: "How long would it take to walk across the Atlantic?"."
- - The answer to that is - 61 days. See: FRENCHMAN FULFILLS LONGTIME DREAM OF MANKIND BY `WALKING' ACROSS ATLANTIC OCEAN IN 61 DAYS | Deseret News