I could be wrong, but this 1984 show - taped from the mixing desk - has not been in wide circulation. At least I've never come across it in 15 years of trading. It's Viareggio, Italy 12 Oct 1984. A lot of Zappaholics don't go for the material and sound from 1984 tour, but I actually think it's ok - different from the '79, '80, '81, '82 purple patch, sure - but pretty fine nevertheless.
Links are in the text file.
Zappa encouraged people to trade recordings of his shows as long as no money passed hands and no official releases were involved.