92 digital dash

first post here so be gentle -- i replaced dash that only had speedo with used one - all gauges seem to work when starting . tach-ok ,voltage- ok ,oil press- ok ,gas - full- but only drove 50 miles - ok , temp - nothing. temp shows "levels" when starting but then nothing .
temp sending unit maybe? wire not connected, and would this be same for gas if nothing happens? thanks

For the temperature gauge, it might be the sending unit or maybe the coolant isn't coming up to normal temperature because of a stuck open thermostat.
The fuel gauge problem may be the sending unit in the fuel tank. I had to replace one on my '97.

if all the guages worked then failed in the first 50 miles I'd say you had a connection that wasn't tight enough and came loose. recheck all your conections that you made when replacing it.