Re: Did Johnson/Evinrude ever make a set of old controls with a key start built in?
If you want the key switch next to the control unit, you might consider making an aluminum or wood box that is just wide enough for the switch and otherwise the same dimensions as a Shipmaster/Simplex box. Set it up to accept the key switch and electric choke toggle. With a couple of bolt holes on both sides of the box, you could mount both it and the control unit with bolts that pass all the way through both.
This would take a little fabrication, but I don't think it would be too difficult.
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