I live at home.
. No idea about the JCM 800; possibly mid-80's.
Yep, all of them have mods. Switched out all the electronics and pickups.
Upgraded all the Gibson with RSGuitarWorks Vintage Wiring kit and the strats with just Paper-In-Oil Capacitors.
The hardware on the Gibsons have been upgraded with Pigtails. (Studs, bushings, tailpiece, bridge, etc.)
Don't get me started on pickups. LOL.