What i would do is don't buy anything and see how it fires. The impco carbs i'm not familiar with so maybe they will be easier starting. If it turns over too many times and you have an electric lockoff then turn the key on and go out and push the primer button on the model e. Then start it... If that does the trick then just either pick up the electric or cable primer. (Or open the hood each time and push the button....lol..) I only have the cable primer on one and it fires decently, within 5 turns.
Do you have a build here for this..? I'd like to see what all is in the kit cary sold you, he seemed like a good guy when i called. He lost me tho saying he never sold the carbs i have and the guy i got my 1st setup from(used) had the receipt...
Oh are you using dual carbs or dual fuel..? If you look in my pics i have a 14 inch air cleaner that fits 2 carbs that is a custom fit for the impco dual adapter. I just bought the base and used my air cleaner instead of buying it all.