4 "non-flashing" red lights in a diamond formation hovering above the Space Needle in Seattle-1971.

I was flying for a regional air taxi out of Bremerton, Washington (flying cargo and passengers back and forth from Seattle/Tacoma Intl.  Airport (SEATAC) to Bremerton, Washington in the Summer of 1971.  I had just departed SEATAC headed West with a passenger in the back seat of my airplane when I looked out the right window towards downtown Seattle and saw 4 red non-blinking lights in a diamond formation over the Space Needle at my altitude.  
I called Seattle Center to ask if they had anything on radar and was told they did not.  I then asked my passenger if he saw the lights and he said yes.  I asked him if he was in a hurry and he said he was not, so I called Seattle Center again and informed them that I would like to divert to investigate these lights over the Space Needle.  
I made a right turn and headed for the Space Needle and the 4 red lights but the closer I got to the lights the more the lights moved upward in front of me.  I attempted to follow the lights but! at about 8000 feet these 4 lights simply vanished in front of me.  I then resumed my flight to Bremerton and have never been able to establish a good identification for these non-flashing, and seemingly connected, 4 red lights to this day.
We spoke via telephone with the witness, and we found him to be exceptionally eloquent and sober-minded.  We suspect that he is an unusually capable, and reliable, witness.  Witness indicates that the date of the event is approximate.  PD