This looks like a Leyland 'Pilot' cab version (1970 - 1975) rather than the later G-cab version (1975 - 1980).
See:-
http://www.aronline.co.uk/blogs/2011...-light-trucks/
(scroll down)
I see that the Terrier name (which had been used for an 11-ton payload six-wheeler before the War) was used to designate the lighter models with the name Laird used for larger models. (?)