I always have the throttle cable hooked to the carb via a relatively stiff spring. That way you don't have to have everything adjusted perfect to prevent breakage and also, you can ensure that your throttle plate is opening 100%. Of course this spring has to be stiffer than your return spring on the carb, or it would just stretch out when you hit the gas. Holes drilled through nuts to hold your cable is a good idea, I was always looking for stuff to hold the cable. Here's a couple pics of my various briggs 5 hp flathead setups. There are better ways to hook the spring to your throttle cable, but I must have thought that was good enough at the time.