Beware of people who say don't service old amps. You might be lucky - but I've opened two amps younger than that and found exploded caps. Then there's the question of old dried out caps and effect on sound. Plus the waxed paper, oil in paper types. One amp, an output transformer leg was open - the guy who rewound it said it appeared that the copper winding had corroded or lacquer gone, but the cap was also popped. That stuff is like acidic Araldite, it took the Hammertone off the case inside. Hate to be digging it out of a fibre board. I think an amp in that category I'd pass on, let someone else keep it as a collectible.