First, I hope all of the US members had a great Thanksgiving. I sure did.
Eric; Thanks for the info on Yukon/Hatton and MER. I will have a conversation with them and Seaboard Marine as I get closer to pulling the trigger. BTW, mine is a full displacement hull, so I'm guessing 8 knots (+- a bit) is hull speed.
And thanks to everyone else for your opinions and experience. At this point, it kind of comes down to the 6B/BT or one of the 4045's. I'm kind of surprised no one tossed in the 4BT. I see TAD has 4BT3.9 rated at 150hp. Any issues with this one, maybe vibration?
I see the 6BT rear turbo model has the same footprint and height as my existing Ford Industrial/Iveco, 40" length x 30" high. The center turbo model is about 9" taller and may be too tall. This is a liner boat and the engine room is pretty tight. With a 10Kw Westerbeke and a 10Hp Baldor electric come-home motor, real-estate is a premium.
John Deere specs shows the 4045's to be 35" length x 36" tall. So it's 5" to 6" taller than the 6BT, but it should still fit. It is only 5" less in length than the 6BT.
I reconsidered part my position on trying to stay away from turbo and electronic/computer engine systems. I have 4 street vehicles that are turbo diesel and all are computer controlled. I have never had a turbo failure on anything, and I know that even if a turbo fails, I can still limp in. But I would still rather stay away from electronic engine systems. I have a real "ghost in the machine" phobia. While I have never had a problem with the Dodge Cummins PU, VW TDi or diesel Mercedes, the Jeep CRD Liberty was a nightmare from the beginning. Poor electrical/mechanical engineering by Chrysler and VM Motors trying meeting US EPA regulations made this great little engine sick and it failed often. I spent a lot of time and $ undoing their mistakes. So rather than having the same potential problems, I'll just stay away from the electronic controlled engines.
Thanks everyone.
Bob