Switching fuels.

What all goes into switching from an alcohol burning motor to running pump gas? Or vise versa. Is it as easy as switching from a hat tunnel ram setup to a single plane carb intake? Or do you have to switch out the whole rotating assembly?

You don't have to change the internal parts at all. If you are running a carb setup,you will need to change that,fuel pump may or may not need to be changed,depends which fuel you go with,fuel filter will need changed. maybe fuel lines.

So say I was running a mechanical injection with a hat, that is only steps it would take?

A couple things come to mind.
If you have an injected alky engine, it most likely has high compression.
You mentioned changing to "pump gas"....which may experience severe detonation on 12...13...14 to 1 ratios.
To change your injected engine to race gasoline, it will just take a different tune-up....nozzle jets, main bypass jet and any high speeds. You will also need to reset idle mixture.
If the engine ran good on alky, with the correct tune, it will run fine on race gas.
Pump gas would probably require lowering the mechanical compression ratio.
Keith