Looks like a B and B hitch so I think that would make it before 1984 ish. Is there a date stamp on the wheels? Our old B and B equipped caravan had shock absorbers and coil spring suspension, that would confirm early 1980's. Have you tried owners clubs and that sort of thing to help date it?
Just took a look at the pictures, and I think that type of windows went out in the 1970s, but I'm sure there's someone on here more knowledgeable than me about that. When did plastic double-glazed windows come in? I always thought it was about 1975.
thanks Dgmm5, I wasn't sure if those lights were original as it seems the front running lights have been replaced at some point.
1978 then wow, that's 15 years before I was born !
will try my best to do it some justice with my over haul, I'm. not sticking to original but aiming to keep it in good taste and solid