The Slingsby T61 is a licence built Scheibe Falke SF25B. As indicated in my post last night the manufacturers never referred to the Falke as a Motorfalke, as this was the Scheibe's designation for the original (grossly underpowered but fun to fly in a masochistic sort of way) different aircraft entirely.
The T61 had the same wing as the German version, Slingsby built a carbon sparred variant for the ATC, and fitted a more powerful engine.
The picture was indeed taken from a T61C (G-BAMB) on approach to Sywell for the 1975 PFA Rally. The aircraft pictured on the incivil beast's link is by coincidence G-BAMB.
If the incivil beast feels generous he may let WZ662 carry on? Over to you.