Hi, Kat Cast another vote for minimal editing, liberal use of periods, judicious use brackets and use of footnotes (or hyperlinks in the case of a CD version). These, for me, take care of inconsistencies and provide clarity without sacrificing the true voice of the speaker/storyteller.
I had the honor and tremendous pleasure of helping a friend's father put together his spoken memoirs during the last few months of his life; a project he had always wanted to do, but had never found time for...until he realized that he had little of it left.
We used a tape recorder, left running and unnoticed in a corner, and simply talked for hours on end (mostly him talking and me listening). Afterward, I would make verbatim transcriptions (with the microcassette player, not a transcriber - somewhat akin to plowing furrows in a stony New England field with a toothpick) and check with him on any questions of fact or points of clarification.
In the end, his family was left with a first hand recollection of a long and eventful life that not only sounded, but looked and felt like the man they had known so well and loved so deeply.
My personal feeling was, and remains, that the summing up of a life in the first person deserves to be conveyed just as it pours forth from the teller's lips...and let the reader decide whether or not to lend an ear to the tale.
Bless you for doing this work in the way your heart directs you. That is the truest guide you could ask for.