I was trying to determine the same thing for Kennedy.
I never got any reply from the local French research group. Its absa39-45 or something like that.
http://www.ww2irishaviation.com/ah920.htm
I guess that in the chaos in the days after the landings remains were found at crashed aircraft and interred in what became the CWGC cemetery. The CWGC site for Kennedy I don't think shows any grave concentration report. So where ever he was found.. he seems to have been buried once with no subsequent re burial... but I'm just guessing.
He may have been found by French police or German military units. The country side must have been dotted with wrecks.