Hi Sam,
I have a set of these on my Cessna 185. They attach on the inboard side of the axle using the axle to gear leg bolts. There is a left and a right part, shaped as an angle so that the attachment for the tow bar, a 1 inch hole, is parallell to the ground. I believe that these were used on Cessna L19 Bird Dogs and are available from a company that rebuilds L19's, Air Repair. Just looking at the axles on a Scout project I have it looks likes the hole spacing is the same, but you would want to verify it.
The down side of using this type of towing arrangement is that it is kind of hard on the tailwheel, as it is intended to have full rudder deflection to release to the castering mode. This does not always happen when you go from forward to backward to push the airplane in the hanger.
Tim