Thanks for the replies guys, just the help I was after.
I'll be towing with the 850 Mike if it's fixed. Sadly my 740 doesn't have a tow bar.
After much discussion with the chaps missus I believe it is
this van, or something very similar to it - lots of models look all the same to me! I'm hoping it isn't quite as big as the one in the picture TBH. Will the weight be ok? I'm planning to do the run in the middle of the night so I should have plenty of margin for error on the various turns/junctions along route