Have you tried rolling off the tone knob? Also, not sure if you know this but the tone knob doesn’t really do much until you roll the volume knob on the guitar back a bit to at least 8 or 9. Then the tone knob does a lot more to the sound. Also, I gotta ask if this is a Sheraton 2 pro or more specifically does it have probuckers or alnico classics. I have owned a few epiphones. And while they can do the job in some instances when uncovered on semi hollow, they are horrible pickups. I would buy a set of used probuckers on reverb for $50. The real issue is gonna be rewiring that semi hollow. I also found that rewiring my epiphones with 50s wiring and full size pots and pio capacitors is another huge upgrade to the tone. Mabye more important than the pickups. Lastly, I would get a Princeton reverb or tweed champ to practice on. I know everybody says tone is in the fingers. But the clearer and better you sound, the easier it will be to hear when your doing it right vs doing it horribly wrong. Btw, tweed amps usually have more mids and less highs than blackface amps but I know you would love either one.
good luck and rock on dude
