1994 grand prix insrument cluster replacemnt

My 1994 grand prix 3.1l automatic trans. car has been in the transmission shop for two months. speed sensor error stops trans fron shifting or working properly. They change speed sensor, but same problem. ( after about 20 miles of driving it does this). They said instrument cluster (speedometer) might be causing this. Problem---- cant find cluster. I found a used cluster but without shift lever indicator. Will they interchage??? My cluster is for on the column shifter while found cluster is for on the floor shifter. Need my car back! any help is appreaciated thanks in advance.

welcome to AF!!!!

I've never heard of a faulty cluster not allowing a tranny to shift properly.