Black rectangular craft over carmichael.

This sighting occured in the fall of 1989. I was working at what was then HomeDepot as a "runner". It was around 9:15-9:30pm, closing time, and I was responsible for "shagging" shopping carts out of the parking lot. Typically during business hours the parking lot flood lights are on to help customers get to there cars. After closing time the lights are turned off at this particular site. While I was out tracking down some carts I happened to look up and noticed a black, rectangular object silently fly directly over head. The object was all black with no running lights. The object made no sound. It appeared very smooth as I did not view any surface features. In fact the only way I noticed it was from the reflection of the street/city lights off the bottom of the craft. I would say the craft was anywhere from 500-1000ft from the ground and maybe 100-150ft across. It was a clear night and the craft was as black as the night sky if not slightly darker. It was heading due North. The whole event lasted about 10secs. Another point of interest is that McClellan AFB is about 1-2 miles west of sighting.
Date is approximate.  PD