Jerry - I agree completely, but the OP was asking about adapters; which is why I posted as I did. I have been suggesting folks to have a professional fill the existing holes, and then modify as required for decades.
Jon.
Good carburetion is fuelish hot air The most expensive carburetor is the wrong one you attempt to modify. If you truly believe "one size fits all," try walking a mile in your spouse's shoes! The Carburetor Shop
