Hello Geraint,
I can't see a crane in the pictures,sorry.I think you might be mistaking the drill rig by the side of the Demag H285s for a crane.We had 2 of them, Compair Holmans, with Cat 3406 engines in them.
The flat bed lorry was an ex falklands Scammell Landtrain,with a Cummins nt855 engine and hiab crane mounted behind the cab.Whenever you got to use it you could be guaranteed of having a wet arse because nobody could get the window to go all the way up.That hiab would easily lift a transmission and diff out of a Cat 777.There was an abundance of those Landtrains about after the war,there was a small fleet of them used by a contractor to take the the coal out of the cut at Budges East Pit site.
Hope this is some help,
Regards,
Mark Williams.