Yeah I have to agree that I think you are probably underestimating the amount of work it is just to put suspension on let alone a motor change.
If you like the idea of rolling your own, and it sounds like you do, I would give serious consideration to duplicating one of the established builds like the dirt ninja or a common bike like the sv650. They are stupid cheap, I just bought an 07 ninja 650 for $560 at a auction.
Try it out on something like that. You'll gain serious experience in what it takes to make one work and if you screw it up it's not that big of a loss. Taking your normal street bike thats worth book value and chopping it up would be a serious mistake especially if you haven't done it before.
Believe me I think it's ambitious and I would never tell someone else it's not possible because thats the challenge. But I've also made a lot of mistakes on my builds fortunately I always bought wrecked bikes for cheap so I could always recoup back a bunch of money by parting it out, but I think you would screw up the value of your bike badly.
Go get a crashed bike for cheap start stockpiling parts for the suspension and get after it, it's a lot of fun and then next year you can tackle your buell
We're not out here to rough it. We're here to smooth it . Things are rough enough in town.