I had that problem too, but only on my '92, not on my '93. On my 92, it only affected the driver info display but not the compass or gages or lighting. When it acted up, the FL driver info display would flicker and show only parts of the car outline, no odometer numbers or anything else, until the car warmed up. It was annoying to say the least...if a warning/error were to occur while the display was malfunctioning, the driver would never know it.
I pulled the cluster and reconnected it and the problem has been gone for the last few years, with the exception of maybe once or twice in the last 6 months.
If it happens again, rather than removing the cluster again I think I'll just try to reach up under the dash and press the connector on the back without removing anything...it'* worth a try.
'99 Bonneville SLE, white, 112,000 miles
'02 Park Avenue Ultra, white diamond pearl, 88,000 miles