Trolling speed control 2 stroke kicker

[JGranat]

Can anybody tell me if there is a way to add trolling speed control to a 2 stroke kicker motor?  I am new to this site, and have found zero on this topic in old topics. I have a 22-ft Starcraft Islander and I use a 15 horsepower Johnson two-stroke kicker I would like to add trolling speed control and steering if possible to this kicker. I have found very little on the internet other than troll Master does not make kits for two stroke motors, can someone please tell me why this is and is it possible to add steering control/precision speed control to a 2-stroke kicker motor?