Hey Adam, there are a few guys that have built hybrid sled/ watercraft engines (I just finished building a 1200 triple) but not in the way that you are describing. I dont know this as a fact but Im fairly sure that a pure WC engine isnt highly renowned for making large amounts of power. The...
I have one for you, I put a 2 speed trans in my scrambler. So I still have the origanal sitting in my shop. I did the swap about a year after I got my quad so it has very low miles. $700.
If your interested send me a PM