I'm convinced that buying a "Torque Monster" flywheel from Truett&Osborn is the best cure against winter-darkness, and it will also stroke your Flathead to boot. Win-Win! Mine is now in the mail headed to Copenhagen. I made my my purchase through Victory Library's ebay shop.
Let me know if you are into something like this, and if so, you might want to check out the Flathead links on this site (left column) if you need some pointers from people who have been tuning Big Twin Flatheads since forever.
I wish I had a video like this for each of this summers trips. It's been great, and can't wait for next year already - however, this season is coming to an end and it's time to break out the tuning kits for some winter-time fun.