I understand that a few Morgans have been converted to 1900 CVH.
I do not have one but i have heard that it is best to ensure that 1900 is the USA inport Pinto engine.
The engine give considerable more torque and power than the 1600. As for thirsty reliablity etc I can not comment.
I had been looking at installing a 1900, and oddly discussed this at Castle Combe with one of the competitors only last saturday, where I was told that the Zetec angine was by far the better bet, so I am back to the drawing board.