Does anyone have the cite for (I think it was) a DOL advisory opinion on the portion of attorney fees that can be charged against a plan for a termination?

See DOL Advisory Opinion 97-03A: http://www.dol.gov/ebsa/programs/ori/advisory97/97-03a.htm

And, 2001-01A: http://www.dol.gov/ebsa/regs/aos/ao2001-01a.html

The hypoteheticals (http://www.dol.gov/ebsa/regs/AOs/settlor_guidance.html) do not deal with plan terminations, but may be helpful.