I have an LT1 from a 97. I was wondering, if I swaped the throtle body with a 93 throtle body, I need less fabrication parts, but my question is... If I got a 58mm Holley would I notice any power gains? If not I may as well just fabricate my 97 throtle body.

 

If you had a heavily modified / built engine or forced induction, it would be more appropriate, but for a stock or anywhere near stock engine, I don't really think you'll notice any power gain. MAFs, bigger throttle bodies are among those highly marketed items that you can throw (a lot of) money at without really getting anywhere. Similar to a $300 intake arm in my opinion..