I made that same mistake in the 80's.. I bought a White "Road Commode" from a local Cummins dealer. They promised me that the engine would perform way past my expectations, and if I had a problem, they would take care of it.. at no cost to me, other than labor.
I explained to them that my loads ran in excess of 150K lbs. many times and that I needed to have confidence in my engine. They said, No Problem, if, after 200,000 miles you have problems, we'll install any Cummins engine you want, as long as your transmission and drive train is rated for it.
After a month, they replaced the engine.
After 3 months they replaced the engine again.
After 8 months, they said, "We'll make you a deal"
The deal was, they put in a Cummins BC II at 375HP, change out the transmission and rear gears, and warrantee the truck as new.
They couldn't handle having to pay a wrecker to come haul me in when the engine trashed out on me by swallowing a valve or even just having one haul me up a hill.
Dallas...an exception to what you wrote on the VT903, (VT 90-Nothing LOL) was that a trucking company I worked for in the 80's and 90's (For 15 years) Thomas Produce, later Thomas Transport, Greensboro, NC bought a bunch in the lates 70's early 80's. Cummins told them for every one they brought in without an overhaul in 1,000,000 miles...they would give them a new one! After what I think was 7 new ones, Cummins said, "Look, we have to stop this!" (We ran west coast, team, we could put a million on in just over 4 years!)
If that engine did not ever run hot, and if the oil was changed regularly...you coundn't stop them!
(Of course when it saw a hill...it jumped into high range reverse!
Most folks I have talked to that had them in their boats love 'em!