I'm trying to figure out if they are auto choke. the start plate i have on the boat isn't for twins. some one took a single start plate and used it. so it has a start key hole, and in the choke push button hole put the second key switch. so i guess it has to have auto choke on them. right?
I've had a 1960 Evinrude 40 hp. Lark, like yours, on my boat since 1963. The original carburetor had an automatic thermostatic choke feature, which was controlled by engine cooling water running through the choke housing. The choke has three settings; off, auto, or manual on. I removed the water housing feature from my carburetor many years ago. It bothered me that the choke stayed partially on far longer than was necessary. But since I still pull on the starter cord, I don't need an auto choke or an electric solenoid controlled choke. I just use the manual choke setting. For your installation, you could use either dual choke buttons, or use a double throw switch to activate one choke, and then the other from a single choke button. Alternately, I guess some ignition switches use an additional key position to activate the electric choke .