Dash lights stopped working

My dash lights and parking lights stopped working  last night. I checked and i have no blown fuses. My HU still lights up, as does the turn signals, check engine lights etc.  I think it might have something to do with something i did yesterday.  One of the previous owners had a sub and amp hooked up and left all the wiring, since im getting a system myself soon i figured id pull out all the old wires.  Thier was a speaker wire that went from the trunk, under the back seat, then under the plastic panel on the floor by where the door closes. Under that the wire was spliced, one part was grounded on a screw, the other was taped to a grey wire. The grey wire went up into the dash, i cut off the speaker wire and all the visible grey wire.  Is it possible the grey wire was the dash lights and was somehow grounded through the speakerwire?

Also, my dash and parking lights where always on, so i think their was always a short somewhere.  I know you guys on here know a lot about car electronics, so i thought you could help me out. The car is a 1991 chevy cavalier if that matters.

the grey illumination wire should have 12 volts on it when the parking lights are engaged... meter the wiring to see if it still does.... there should be a separate fuse just for the dash lights which is low current ( usually around 5 amps ) which you may have missed and may be blown.....

also look for this... there are TWO grey wires and two Yellow wires at the radio harness... the previous owner may have the grey ILLUMINATION wire hooked up as a speaker wire... meter BOTH grey wires at the radio harness for 12 volts with the lights turned on and see which one has 12 volts on it... this is the proper illumination wire... just cap it if unused.......

Your left front speaker has a gray and so does the illumination to the head unit.  The parking light should be a brown wire off the back of the switch.  Leave it up to the design team to put the same colored wires in the same area when every other wire has a different stripe on it!

I would never recomend it, but I have seen the dash/park light + used as a remote turn on for an amp.

Or as a relay switch wire for other lighting (neon,LED?)

The only way to get to the bottom of this mess is to test and chase the wires, no quick fix here, sorry.