(SPOILER)I am not sure how much weapons matter because you can't use the attack command, so apart from any stat upgrades you might get, I think you are fine. In terms of levels, I think you are at least 5 above him right now, maybe a bit less, but you should be fine.

I beat him by following the strat guide and spamming Souleater, and I think if you follow that tactic, levels are not as much a factor in this fight as they are in some others (like Ultima and Zodiark).