Quick question about X-2 (possable spoilers)

I’m at the part just before you go to the Farplane on chapter 5 and I need to do some serious levelng up. I’m only level 31 and need to get to at least 65 or something. I just wondered where are some good places to level up?

The Thunder Plains New Cave is a good place to level up. You may also want to try the Bevelle 100-level dungeon.

I beat the game with Level 45 using 2 Dark Knights and one Berserker.