You can't put the thermostat in the wrong way round (i.e. upside down) but there is a circular recess in the top half of the housing where the thermostat should sit. The circular rubber seal should be in the lower housing with the thermostat sitting in it. Well this is how mine is now.
I am just going on a 120 mile round trip to Clun to see the Green Man expel winter by throwing the frost fairy into the river

, its something the wife wants to see. I hope we don;t overheat on the way but you cotta go for it and I'm sure the Bongo will perform admirably.
Will let you know this evening.