6 inch risers were not going to be enough, and nobody wants to sell 8 inch risers for a reasonable price (6 inch are 80 bucks, but 8 inch are around 200 bucks! It's a simple metal rod!). So I figured it would be better anyway to reuse more of the original bike and make risers that functioned as an adapter between the stock Yamaha risers and Harley's riser bolts. I figured why weld when you can just screw things together?
So here's the design I came up with:

Jared helped out a lot on this one by drilling all the holes, which was mostly a challenge in eyeballing "straight and centered" using a drill press where no two pieces were exactly parallel and nothing was quite level. While he was working on each riser, I tapped the holes in the other riser so the bolts would simply thread in.
To get this done I just needed the appropriate taps, a tap wrench, etc... Oh, and a thread comb so I could identify the thread spec of the bolts I needed to match in the first place. Here's all the information you could need about threads, fasteners, tap hole bit sizes, etc, (metric and imperial):
BoltDepot.com Fastener Info

With the risers on and tank in place, here's how the cockpit is looking:
So here's how the bike looks so far:

email: mikebike@rocketcar.net