R20 ...
BEagle is correct in saying that there was never a 3rd rear seat option for the RAF Bulldog. It was the Swedish variant that had the 3rd rear seat ... along with a few airframes equipped to fire rockets
More here ...
FPL 61C Bulldog - page 1
PS. Having seen a certain John
Pr***e lash his kit down in the back of a ULAS Bulldog in the mid 70's ... It's clear the anchor points were of great utility
If my memory is correct, that early UHF lash-up BEagle mentions ... was exactly that ... the anti vibration mounts and restraining strap looked very much like an after thought mod
Coff.