IIRC you can tow a trailer that doesnt weigh more than 750 kg laden, I did my trailer test as i used to work in a body shop and fell into to above entioned catergory for people who passed here test after 1997 and Occasionally i drove a shogun with a bryan james transporter on the back.

Dont know if it matters as the spec is part of the truck isnt it??

Slightly off subject thjough but one of the other lads told me if you were driving the 7.5 tonne tilt and slide and you put a caravan on the tow hitch to pull behind that you had to have a hgv artic licence??
Not 100% sure if i beleive him