just to add to that, yes the differences have been pointed out but they were not made my different companies.
they were all made in the same place, they just had the different badges and grilles fitted. actually they would have been made at longbridge, just like your advantage.
Austin, Morris, Riley and wolseley are all companies that were part of BMC (the British motor corporation).
there are quite a few cars that were basically the same but made under the different names with simple grille and cosmetic differences.
elf's and hornets are quite simply minis with different fronts and rear ends, just like the clubman