Keep in mind that what you have inside your gas pump is first a motor, the belt from the motor turns the pump. The pump, pumps product up to the meter. While most will call the V/R the meter, the big thing just below it is actually the meter, and this is what it was called when the pump was new.
Both the pump and the meter probably has some very old, very bad smelling gasoline in them. So, assuming you want to keep the pump original and want to leave everything in it, you need to take the pump and the meter apart to make sure there is no old gasoline in them. Imagine you selling the pump without doing this, and for some reason the buyer turns the pulley on the pump and some of that old gasoline comes out the pipe on to his game room floor.
In 25 years of messing with these pumps I have heard every reason why you should or shouldn't leave the parts in the pump. The worst argument is "you should leave the parts in the pump in case someone wants to hook up the pump and use it." Believe me, between EPA and state and local laws, your pump will never pump an ounce of gasoline in the future.
So now, the decision is yours.
Jack Sim
Author, 1st & 2nd editions of Gas Pump ID book, 3rd edition is now available at
www.gaspumpbible.comAir Meter ID book also available