[Cal Metal]

Reverse gear is situtated on the 1st/2nd gear synchro. Its teeth are straight cut, so that is easy to spot. If you turn the input and the tail shaft turns in the opposite direction, you know you are in reverse. The middle shifting lever or cam on the side of the case is the one, then, to rotate to get the unit in neutral.

When looking at the gears from the top, the synchro units should be evenly spaced between each gear. If not, one is probably engaged. You can see the difference, as one will be locked in and one will be locked out. The sliding clutch, in neutral, is evenly spaced between the two gears (lst/2nd) and (3rd/4th).

If they are equally spaced, and you can spin the input while holding the output stationary, you are in neutral, assuming reverse is not engaged.