I had seen that crank a few weeks ago but couldnt find on MWSC lately awsome it is still available. The flywheel I am planning to use in from Zach Kerber Machine and seems to be 6 lbs but I hope it can be lightened. Billet Aluminum Ring Gear Flywheel@philr, here's a link to ARC racing's lightweight aluminum flywheel for Kohler V twins:
ARC Billet Flywheel Kohler V-Twin 6611-KVwww.arcracing.com
And, here's the link to the 3" stroker crank. Midwest Super Cub has just about everything, including advice, that you'll need for Kohler V twins.