Only just found your video as I've found a forward control motor that is a really good price that I'm looking for a way to convert to tiller just like this.
That's cool. I have a 35hp Johnson and did basically the same. Bolted a 1/8th u channel to the engine. Cut out about one inch of the front top so the square tubing can pivot up. One bolt through the u channel and square tubing. I left the key set up . Drilled off the tit on the throttle hook up and installed a rodend bearing. I've got a throttle cable from a Cessna 152 clamped to the square tubing. Looks funny but it saved me 600 bucks or so. All my parts are aluminum. I thought about a motorcycle throttle but mine pushes open and its stiff. Be creative.
Great video, but I have one critique, you really want to try and go the modern route, don't want to have an incident where you get thrown off the boat and you didn't hit the kill switch. Saw a video of some coast guard having to chase down a boat with a similar setup where the operator got tossed. Fortunately nobody got hurt in that but it's something you should consider. Cost is under $20 a kill switch and lanyard.
I wouldve rigged the thing to a new steering sytem if i was you.. I have a dinghy and i always wanted to setup a steering wheel but i dont see a good way to do that
