That’s cool! Alot of ntsc consoles are identical between Japanese and NA with just a jumper or easy change needed to switch between the two.
I remember a buddy and I downloading Congo, burning it to a cd and spending an entire day trying to get the swap method to work. We were so ecstatic when we finally got it working but our joy quickly turned to dissapointment when we learned just how bad Congo fucking sucks. To this day it’s still our bench mark for a game. Like “yeah mass effect Andromeda was terrible but it’s not as bad as Congo”