[Steve@OldSub.com]

Anything can be done with enough time and money.

I'm not real familiar with the C5 dash but in the early 90's most GM dashes used a digital input for the speedometer and tach, but the rest of the gauges just used sensors on the motor.

The C4 digital dash would be more complicated, since all the gauges are digital and require some electronics to work.

Find someone with a C5 factory repair manual and look at the wiring diagrams. You might develop some eye-strain, but should be able to determine if the oil pressure and water temp and volt meter are going through the computer or not.

Otherwise your easiest option would be to start with a wrecked C5 and swap the motor and associated wiring to support the dash. Be aware the C5 uses a rear mounted transmission so swapping all the driveline means dealing with that issue.