Personally I think that the only proper way to do it is to pull the pipes off and manually rotate the valves to fully open. If you shine a torch up the flue you'll be able to set them pretty accurately. They want to be just right, or maybe even a fraction (0.1~0.2mm) above the port. Now scribe a line on the back plate of the RC valve pulley holder thingy so that you can clearly see the exact fully open position.

Put everything back together, start the bike and let it run in the 2~3000rpm range where the valves will move to full open, and you can tickle the adjusters up to make sure it aligns perfectly with your mark. Don't over tension the cables.

A few blips of the throttle will let the valves cycle open and closed, and then check again in the 2~3k range. If all's well lock up the adjusters and go out and ride the thing.

If you've got too much money then once you've got this far throw it on the dyno and have a fiddle. Just half a turn here and there can make a difference but you can get it pretty close to start with.