I hooked up my shift light but I ran it to the fuse box. Dont do that lol. Im going to redo it when i put my water, oil, and nre reverse glow gauges in. But i would try the wire for the vert top. its right by the ash tray and you can pretty easily just run a wire up behind the radio and up through the clock if thats where you are running it. As for the ground, I just drilled a hole in the big metal tube behind the cluster and grounded it there.
EDIT; For the lighting source pull the cluster and find out which wire on the headlight switch turns hot with the parking lights on.