I just discovered this apparently forgotten puzzle. I can't believe someone hasn't tried the obvious, but since they haven't, I will. It has been established that it is an MG sports chassis (not family) from the 1940's, customized in Australia. By my reasoning, if it is an MG sports chassis from the 1940's it must be a TC (it could be a very late TB, but that would be very unlikely). So I will say a: 1940's ('45-'49) MG-TC with a customized body (I have no idea who the customizer might be - it might be a homebuilt).