Troubleshooting Dash light/hvac light/cluster light circuit

[McWattersJ]

Using the ETM, for my 88 Vert, and a Digital multi meter i have have been attempting to figure out why none of my dash/cluster/hvac/ash tray lights work. I have replaced burnt bulbs.

The RED /Gray wire feeds all of the lights and a BROWN/White goes from the other end of each light heading to a splice then to the rheostat, then to ground.

When I pull the headlight switch into position 1, I have voltage on all of the RED/gray wires at each bulb, when measuring from ground to the red/gray. But nothing lights up,

at the bulb socket, when i measure from the REG/Gray to Brown White i do not have any voltage...

Im thinking theres something wrong with my rheostat/headlight switch.

The one thing that i do not get.... when my headlight switch is off(position 0) and I check for continuity between ground and the RED/Grey wire, my multi meter bleeps, indicating that there is continuity, which would mean there is a point where the RED/GRAY is touching ground, which then should mean its a short. If that is the case should the fuse not blow? resulting in no voltage at all when I pull the switch to position 1 or 2.

Its driving me nuts, I should probably try to source a working headlight switch to test but they are hard to come by here In Ottawa, Canada

any insight is greatly appreciated.

[McWattersJ]

Update! After taking apart my headlight switch I've found a break in coil of the rheostat, there was no ground reference for the entire dash light circuit. I attempted to solder the broken section . The coil resisted greatly however I managed to make a bridge, without ruining the functionality of the rheostat. I could have easily bypassed the coil however that would mean the lights would be full bright all the time. Testing tonight !

I made an album with details in regards to taking apart the headlight switch check it out

http://imgur.com/a/9brdS