I don't know enough about the construction of the side-crank models to help, except to suggest that it might be necessary to drill out some rivets or other connectors to get the handle off. I would imagine you could leave the other gearing in place and make a drill adaptor that would go on from the side. Wish I knew how to advise you further. Others here will be along to help I'm sure.
It's never too late to have a happy childhood!
Lee, WU0V, and Courtenay, N0ZDT
2011 Rockwood A128
2000 Silverado 1500 pickup
60W solar system
2000W inverter generator