The question you have to ask yourself is: Will the engine be able to utilize the greater flow capacity of the larger throttle body? If the answer is no, then it's a waste of time and money making the change.

The same holds true with carburetors. I've known guys with a bone stock AMC 304 replace the MC2100 2-bbl carb on their engine with a different manifold and a 750 CFM Holley 4-bbl carb. There's no way that 304 can unilize that much flow, unless it gets some major engine modifications involving valve timing, porting and polishing, etc. Even then, a 600 cfm carb would be plenty. For the stock 304, even if they wanted a 4-bbl carb, a 390 cfm or 470 cfm would be plenty. Actually, the original MC2100 2-bbl is well suited to that engine.

So, before you go to the trouble of adapting a larger throttle body, I'd suggest you find out how much flow your present TB gives, how much flow the TB you're considering gives, and how much your engine can even utilize.