Don't expect this kit to be available right away. We are looking at machine work and metal treatment done across Orange County California (at three locations), with plans being drawn up and CNC programming set up in the Mid-West. Expect a thousand dollars exchange plus shipping and a month turn-around. Be delighted when it turns out to be a lot less and a lot faster. That's all I can tell you for now; work is in progress.
Keep in mind that this leaves you short a wheel that will fit, sprockets, chain guards, and swing arm modifications or replacement. Plus a ton of tinkering to dial in gearing. Remember, the swap involves taking your engine completely apart and putting it all the way back together. A good opportunity to really dump some performance enhancement into it. Consider cams, BIG bore pistons, we'll probably have stroker cranks available by the time this kit is available, and if you like to tinker: EFI.
Hold the presses: it look like a relatively straightforward change ONLY on Gen I Viragos. Looking at the left rear frame mounts on the thousand and eleven hundred, it appears that there is too little room to mount a front sprocket of any size. It looks like some sort of "transfer" case must be interposed between the engine output and the front drive sprocket. Which means that the chain (or belt) would have to go on the right side of the bike, and the wheelbase stretched by a couple of inches. I've got to do a little think-work, perhaps a two stage shaft could run concentrically with the (new) swing arm pivot -- a small sprocket on the engine chained to a small sprocket toward the rear, turning (on the same shaft) a larger sprocket. If you have a Gen II or later, go look at the left rear mount lugs on the shaft housing. All those holes must be present to hold in the engine. Your thoughts are welcome.