I have a '70's Ampeg V48 amp that has been sitting for 20 years. I would like to use it again. Do I: Just turn it on and see what happens? Thoroughly remove all the dust, then turn it on and see what happens? Take it to a repair person, let them check it out and do maintenance, then bring it home, turn it on, and see what happens? I'm leaning towards the latter. What do you think?