I have been tightening all of the accessible housing screws as part of an amplifier service, especially the speaker mounting screws and baffle screws to compensate for the housing wood shrinking over time.
Uhhh, players used to call that amp the baby twin! One of my favorite black face amps! You should check out Lyle at Psionic Audio on RU-vid. He,s a ,Memphis amp teck and an expert Fender and Vox tech.