By just looking at the power steering reservoir, you can't necessarily tell if there is ACE or not.
The Series 2A V8 Disco has a power steering reservoir but does NOT have the 2nd cap for ACE. You can do as previously mentioned and check for the hydraulic ram on the drivers side, look for the ACE pump, or watch if there is a ACE light that does a self test when starting the vehicle.
Cheers.

