I have no experience with re-power diesel for diesel. But a few years ago we did some extensive research on repowering from gasoline to diesel. Our 40' Tollycraft has 440 CI Chrysler gasoline engines. We assumed new diesels and a paid-for professional installation. In 3 separate estimates the costs ran about $80,000.00. Of course there is a heck of a lot more to do when going from gasoline to diesel so that's not a good comparison. As reported here several times, the costs and expected benefits to accomplish this were so completely outweighed by keeping the gas engines, that it was ludicrous to consider. The figures that I vaguely remember were. Fuel cost differences for 30 years, 3 new pairs of gas engine long blocks installed over that time, include difference in resale value, still did not come to 1/2 the costs of doing the conversion. Joe Engel