I've been looking at doing the same type of conversion, and the long and short of it is that you'll need to basically design an entire new cradle for the motor in order to get the swing arm pivot and counter shaft sprocket in the right relationship. Then, you can hang all the LC4 suspension bits and bobs off of it. If you're designing from scratch, you can do neat things like adjustable height swingarm pivots to change squat characteristics.
This is really a positive.
Also, consider tipping the engine more vertically - viewed from the left, clockwise. That should help lower the sprocket.
When the sprocket and swingarm pivot are properly aligned, you wind up with not very much ground clearance because the street-oriented motor isn't designed with ground clearance in mind.
How much stuff on the bottom of the motor projects into that oil pan? Can you just fly cut the entire bottom of the pan an inch shorter and weld a new floor into it? A side-view photo of the bottom of the engine would be nice.
Nice mill - is it a Deckel?
When they say Harleys are for 1%ers, I don't think they mean guys who sell crank and get in bar fights any more.