well vccomm.
thats sounds like a reasonable explanation to me.
so the better design gets first release.
maybe the new released sheerline did indeed have the longer cowl and later engine mk10. with probably slight modification to the magneto as in the 5e .to accomodate the longer cowls shape.
then as you suggested the other variants (developed at the same time)use the square cowl for the impulse starter etc.
they surely would have had more than 1 engineer working on a design?
we do know that much later down the track they start putting all their fuel tanks under the cowl.
which brings me to another question what really is the difference between a mk9 and mk10 engine. other than to accommodate different cowl shapes?
sorry for my speculative ramblings guys. i am just excited and curious. bazz
