Yep, you've got the order correct - reading from the front = Red, Green, Amber (stop light orange).
The actual display sequence was governed by the Colours of the Day Order, which changed at least two or three times in a 12 hour period, the times pre-notified in the Order. The sequence of lights shown, when required, was controlled by the I.D. Lamps switch in the cockpit, allowing, for example, flashing Red, or maybe steady Red/Amber, or flashing etc etc.