Out of curiosity, I found an old ITG2 cabinet (installed, FYI, at Kidstar inside the flea market), and noticed the monitor was too green. And for those who rush in this answer, it's not an ITG hack at all. Does the machine really have a tint setting? Sorry if I'm a bit of a noob when it comes to arcade cabinets.
Also, you may want to check the G wire on the chasis. Test for continuity. If it's bad, re-solder it. Just make sure you discharge the monitor before you do any of this stuff OR YOU WILL DIE! I don't want to be responsible for your death.
it might be, but that's usually only if their are discolored blotches, not the whole monitor. But it still might be a good idea to try if the cap kit doesn't work.