That is an interesting photo. Look how they tapped up the headlight.
Vegamótastígur means = Crossroadstreet. This photo is taken on that
street in Reykjavik ca. 1940-41. 79 unit insignia is for a Military
Police unit based in Iceland. I have more photos from this unit in
Iceland. Any one know anymore about them?
'79' is indeed the Arm of Service serial for a divisional provost company in the 1941 serials (presumably, in this case 49 Div. Provost / Alabaster Force ?)The cap badge is also clearly CMP and the lance-corporal's stripe fits as well.
I'm not sure about the pillion pasenger. Is he wearing an army uniform or denims ? Could he be a matelot or Merchant Navy with some sort of acquired badge on his hat ?