Luckily I still have the VHS, though the first TV showing of the documentary was even longer still (by about 10 mins). This one additionally featured a sadly ailing Mercedes McCambridge and (briefly) James Ferman.
Apparently McCambridge's family asked for her footage to be removed for the VHS (ie 74 min) version. No idea where Ferman's footage went though. I guess the distributors cut it.