Hi Mark, your machine is later than I thought; your engine was manufactured on the 27th August 1975 in the US., was shipped to Australia and was placed on the chassis probably later that year or early 1976.
My thoughts are now that she
is a Series 2 machine that has had the engine deck replaced (that might be the reason that the ID plate is missing) but that is a good thing, because as I have explained the twin rail system is prone to cracking.
She is a beauty, and will come up a treat with some TLC!
