Starter Generator for Pony Motor

has anyone tried mounting starter-generator, such as those used on 11hp golf carts or 600cc Haflingers engines to convert a pony motor to electric start?

I realise that a regulator etc will be needed and that charging time may be an issue in that the pony motor would need to be run for a while to charge up the battery after use, but it might prove to be a neat solution given the genuine generator and electric starters are virtually obselete here in Aus nowadays.

Or am I mad😊

Here in the U.S. some of the small engine manufacturers adapted "Starter-Generators" on their engines to get into the Lawn & Garden Tractor market. I had one on the shelf for a long time before installing it on my Portable Welder. I could have very easily figured out a place to mount it on a CAT for the Pony as it is about the same size.
So you are not "Totally Crazy"
😆