Staghound Hydramatic Transmission Question

[Malcolm Towrie]

I'm working on a Staghound. Both Hydramatic transmissions have a fitting on top of the transmission that provides a pressure tap for the output of the two oil pumps. The fitting is located between the two indicating pins for band adjustment.
These taps are each connected to a pressure switch with a set point of 60 psi. This is identical to our Chaffee tank, where the pressure switches are used to drive warning lights on the instrument panel which light if the transmission line pressure drops below 60 psi. They also prevent each engine start switch from working on the basis that if the pressure switch contacts are open, ie pressure is greater than 60 psi, the engine is already running.

However, my problem is the only manual I have, TM9-741 (I can't find any manuals specific to engine or transmission overhaul) makes no mention of these pressure switches, and there are no warning lights on the instrument panel for low transmission pressure. And there's no evidence of added panels with warning lights.
Was this a later modification? What am I missing here?

Perhaps the pressure switches' only job was to prevent starting an already running engine?
The wiring on this Staghound is rough so it could be the warning lights were in a separate panel that no longer exists.
Thanks,
Malcolm