OK, essay time, having completed siesta!
Once upon a time.....
That green on the model looks just right, as do the “snail” and number in terms of size and shape etc. The “snail” is indeed the right way round; with extremely few exceptions they were always that way round, with upper bit left, and lower bit right.
One of the few exceptions was the OTHER side of tenders, where the upper but was to the right, i.e. pointing forward; the other such exception was the driver’s side of buses and trucks.
I can’t tell from the photo above whether the logo on the tender is a yellowy or light green colour. It should be light green; it's worth pointing out here that some model K1 class 2.6.0s (the black ones) and an old Lima 0.6.0 were made with yellow or white flying snails; these are ENTIRELY wrong in all instances. The "snail" logos were a transfer, same as used on buses, and were applied to tenders of green, grey or black variety - thus the flying snail should always be light green, as in this case the number also. Numbers were the same light green on GREEN engines, but pale yellow on grey or black engines!