No I don't think it is a later type Gareth. It is EMER WHEELED VEHICLES U 209 Misc Instr No.5 April 1966 for Trailer, 1/2 Ton, 2 Wh, Mk 1, All types (Post War Pattern)
The actual draught eye is LV9/BTR FV11520 or FV11558
The next Misc Instr refers to Mk 2 & later Mk 1 fitted with LV9/BTR/FV183470 refers to fitting a slotted nut with a hole drilled in the shaft for a split pin.