Putting this out to a wider audience than the Forum I've been discussing it on. I'm sure there will some suggestions. @Chris ? Two attached images. The first a rather atmospheric photo of a normal British High Street in possibly the 50s. The second a blown up part of it showing the rear end of an odd van. The Added headlights could simply be a reversing aid for in the dark, reversing lights weren't on vehicles back then. But it's an obviously fabricated rear door with a big hole. Could it simply be a carpet fitter who carries long rolls of carpet? And what about the tube/grab rail along the side of the van? Anyone seen anything like it before? For reference, here starting on post #7,185. (I'm DesmoDog on there as Nasher was already taken) https://www.motorhomefun.co.uk/forum/threads/born-in-40s-50s-60s.301634/page-240#post-6921487
I reckon it's most likely exactly what you've suggested. An old van (it appears to be sign-written) that someone has modified to suit their trade. The '50's were very much the make-do-and-mend decade, with very few elf 'n' safety regulations. Could have been a carpet fitter. Or a plumber or carpenter. Anyone who needed to carry long lengths of material about and the rear facing headlights might have doubled as work lights.
I know there were many Special utility adaptions over the years, could have been second world war related, or more likely for some trade purpose - Post Office certainly adapted smaller vehicles. The twin rear facing lights add a valuable clue and rule out a few suggestions. Between us and the "internet" - i'm sure we'll crack it. On further inspection, i don't think we can rule out a bit of pre-AI picture tampering also - is it a hole? was popular (npi) for spare wheel to be mounted here..
another clue might be the pipe/tube running along the right hand side, maybe going into the driver's window. Apart from an attempt at gassing himself, i wonder if the owner ran it on gas? - doesn't explain the headlamps or the "hole" maybe.
Vans always had double doors with side hinges and a vertical split in the centre in those days. On this vehicle both doors have been removed and replaced by a single part, with what appears to be a windscreen and white lamps. As though the van was going to be driven backwards a lot.
More than likely AI sh*t . Average working man couldn't afford a car or van back then. Motor bike combo at best. Could be be gas turbine space vehicle?
First van on the left, as mentioned been adapted for a certain trade with front lights put to the rear
A photograph taken of Above Bar, Southampton, mid to late 1950’s, published in a local Echo newspaper as part of an historical retrospective. Contemporary to @Nasher’s post to the day, if not the hour or even the minute ? Unfortunately, Google also found several pictures of the same subject matter but with different descriptions and different dates, mostly posted on FB. Andy
Good find Andy! Hopefully there is more to find - you can make out some "equipment" on the road behind the van and possibly something tall between the "lady"* and the van.