If you still have all the original parts, it might make a difference. If you have to buy the original parts and pay someone to do the work, you might not get a return on your investment. Do you know if there were other performance modifications to the engine? If it has a performance camshaft (quite possible since often done to get most out of the bigger carb) and runs more advanced timing, the original carb may not work well with the other mods.
If you can find a carb knowledgeable mechanic it might be possible to disable your secondary barrels. The primary barrels run the truck and the secondaries (which are much bigger) kick in when you press down on the gas petal. Sometimes the secondaries are opened by a mechanical linkage, and in other carbs they secondaries are sucked open by vacuum pressure.
If you can find a way to keep the secondaries off line, you’ll save gas. Of course, when you want power you’ll have to live with a lot less of that.