[modela-carb]

There are 4 plugs...2 in the lower casting on either side and 2 in the upper casting, a small one under the idle air screw and a larger one at the top under the front manifold mounting flange. Use care when drilling the plugs. Start small (7/64) & work up through 9/64. Often the old plug will spin out with the 9/64. If it doesn't & you have to use the 1/8, be sure you're going in straight as it is easy to wind up with a hole that's too large for the new plug.

& I second 30Cabriolet's comments