Warning do not get the white face clusters as they are different from the normal black ones dont ask how or why they electronically the same but do not work. I have 2 clusters and they do not work like the regular black backed clusters
I know this is an old post but figured i would add to the discussion 6 years later lol:
Not sure which white face cluster you used, but i recently installed a white gauge cluster that i got from a 91 eagle summit, built at the dsm plant, and you might be on to something, i installed it and it did not work at first i checked the dash tach signal on the car i got the cluster from, and the wiring is 100% the same as a base or c53a gt colt, so i took the cluster out and noticed the screws on the back were a smidge loose, i tightened them snug and it sort of worked then went out...i lightly shifted the cluster not tap, lightly left and right then it worked i think there must be something wrong in the contacts on the back of the cluster, or the dash wire connector on the back of the cluster, so this should be inspected before claiming they don't work 100%.
i am still working with it so will update if i find out what is causing it.