It is on the M. Not sure about the 40, but IIRC that is the same. The 420 and up have R the same as 2nd.
Now that begs my question. Is it R=1st on the 4 speeds and R=2nd on the 5 speeds?
I seem to recall that the 4 speed went to R=2nd for the 420.
I know R=1st on the M 4-speed. I was whining about my M being too slow in R just today, in fact! I jumped off the M and onto the 420c where I have a reverser and was happily backing up in 3rd as I was doing a little brush swatting, which I do in 3rd. Nice!

Of course, the data is all out in my shop in the manuals. But I am happily in the house now and too lazy to go looking thru the 40 and 420 shop manuals....
