I picked about $10 worth of electrical conduit and fittings and welded up a tow bar down at the TechShop. The crosspiece that you see in the center can slide up and down the tubes to apply the clamping force that will keep the tow bar attached to the tailwheel bolt. This should be super simple to attach and remove. Basically, you just line up the fittings with the bolt and squeeze the tubes together. The crosspiece will automatically slide down the tubes and lock the tow bar in place. To release, just pull back on the cross piece and the fittings will pop off. I made the tow bar 5′ long because a shorter tow bar tends to hit the bottom of the rudder. Hopefully 5′ will be long enough to avoid that.