Steve
You might already have this - it's the formal report into the accident
Air Accidents Investigation Branch: 4/1974 G-AOHI
There's still aircraft remains on Ben More - a few years ago I could identify Dart combustion chambers and what I thought were spar web caps complete with red paint.
My father-in-law is ex-BEA and was involved at the time in assisting with the recovery of the aircraft. He does remember small pieces of the aircraft remaining on the hillside and being gathered together in a pile and left. Presumably that's what I saw.
Ben More can be a tough, unrelenting climb at the best of times but these small pieces I'm sure will still be there.
Will ask my F-I-L for more info, but as an ex-engineer I doubt he'll have pictures of aircrew.
Good luck.