If you look in the Ground Distribution part of the ETM - the first page lists the ground points and their relative pages. The next pages go on to detail what is connected to what ground.
You can then look at the location views to reference the ground number, and then a picture of where it is on the vehicle.
For example:
All of the LH Front Lamps join up to a bunch of other underbonnet bits, and all go to E0154 (up to 1999) or E0557 (99 on)
All of the RH Front Lamps go to E181 (up to 1999) or E0560 (99 on)
All of the RH Rear Lamps, Lower Tailgate lights, Number Plate lamps, and Hi-Stop lamp go to E322 (up to 1999) or E0565 (99 on)
All of the LH Rear Lamps go to E367 (up to 1999) or E0809 (99 on)
You should be able to cross reference those ground points in the location views in RAVE so you know where abouts on the vehicle you are looking.
Marty