When I first crank my 1990 LS 400, the Reverse, Neutral, and Drive lights do not illuminate on the Instrument Cluster panel; but after the car warms up, they begin to work fine. If I jiggle the Shifter handle, the Neutral and Drive lights will flutter on for a second or two, but then they go off when the jiggling stops. The Reverse light does not respond to jiggling the Shifter handle, and the Reverse tail lights also do not work until the car warms up and the Shifter lights start working. I have no problems with Park, 2nd, and Low. For the record, I have read thru all of the threads here and have not spotted anyone else having this exact problem. I have checked the left trunk hinge wires, and they are ok; and I have replaced the Instrument Cluster panel with one with just 77,000 miles, but these problems remain. Does anyone have any ideas on what might be causing this? Thanks!