Hi Phil,
The devil is in the detail!
Each of the Sharks in the photos you have is different.
First - EWS livery, no rainstrips, covered chimney hole, Air fitted, unbraked.
Second - Loadhaul livery, 2 piece rainstips (BOTH ANGLED SAME), covered chimney hole, partial sheet material ends and sides with additional end bracing, Air fitted, unbraked.
Third - Dutch livery, 2 rainstrips (Opposite angle), covered chimney hole, lookoout ducket removed, looks like end is sheet material, Air fitted, unbraked.
Fourth - EWS livery, 3 piece rainstrips, covered chimney hole, partial sheet material sides and ends, Air fitted, unbraked. In addition appears to have replacement or replacement supports for the end further away!
All in all...
An interesting quartet!
Unable to tell if the flat sheeting is ply or metal.
Thanks
until