Hello Colin,
I have picked up on your message concerning the nose cone and a cowling that goes under the grill ? Could you elaborate a bit more for me please. The reason for asking, there is no cowling as such under the radiator grill. There are two types of radiator grill fitted to the M types. One is the waterfall grill that sweeps up over the nose cone, the second is the lower grill type that just covers the opening in the nose cone.At the back of the radiator grill there should be a small half moon shelf , this is riveted to the radiator grill bars to help hold them in place. This small shelf is fitted to both types of grill, is it this that you are referring to.