I think this is a bad sign....the Petty group was very surround friendly and this would have been a great opportunity to get these last recordings out in a mega box set...and they didn't think it was worthwhile....check this out
Why do you say that? It's all out takes and live stuff, right?
Are you saying it all could have been included as bonus material in a box set which would have also included 5.1 studio remixes?
Or are you saying this material could have been mixed in 5.1 and released along with the stereo version?
I'm not sure its an issue if its the latter scenario. And IIRC none of the Petty 5.1 releases included any bonus material anyway.