I just finished soloing the Ancient Papyrus (MNK50/PLD25) and I had some thoughts on it.
First is location. The best place to fight these guys is the enterance to the Eldieme Necropolis which is accessable through the Beaucedine Glacier, the one furthest from Jeuno. It's a long run, but worth it. Near the enterance, there are two side rooms, each with a lich and a pair of hell hounds patroling the hall outside.
My strategy was to build up TP on one of the hounds first and then boost like crazy before hitting one of the lichs with a chi blast. The mummys in the rooms will not agro for that. Invariably the lich will start casting a spell (I found you can run out of range of freeze before he can finish).
As far as the fight goes, you can take that as best you feel, but if you get in trouble, you can easily zone. I was able to beat it a few times without even needing 100 fists, though mostly this was on lightsday.
After the 8th fight, I got my Ancient Papyrus.