I just published a Challenge article in which I admit that summers past are all a blur to me, so I'm not the best person to answer the question, but all historians (according to Hayden White) fudge the events they write about. From my perspectivist perspective, this doesn't mean that there is no truth, just that history is inevitably at least one remove away from truth.

I have only intuition here, but my money's on Hal Ashby for the soundtrack choice (I've never seen Shampoo, but just looked up the songs--what a fantastic collection).