Was looking for one last year myself when adding trans/diff tem gauges to the Durango. Being a lazy guy, I used one of those blade-type fuse power taps on an unused fuse slot in the fuse box on the driver's side of the dash. The box that's accessible only when the driver's door's open. Prodded around with multi-meter to find one that that was only on with the key on. Ran the resulting power wire up the door jamb trim to the dash-mounted pod, wires for the probes down the same route and through the firewall left and below the column.
I know it's not the same body/year, but it's an idea.
