If removed I install a used Inst cluster will the mileage show from the car it was from or my car?

computer

remove inst. cluster. problem is most likely in inst. cluster itself. dealership can send off for repair if this is the case.

inst. cluster

you need a new inst. cluster

The New/used cluster mileage will show up. However I can reprogram your cluster to the correct mileage from a new or used cluster.

no your mileage will stay the same. Your actual mileage is stored in your vehicles computer (ecm) your cluster just displays the information

it sounds like your speedometer head has a internal fault your probably gonna have to replace it,you may want to remove it and check that all of the plugins in the back of it are inserted fully

The mileage on your new (used) instrument cluster will show the mileage from the car it came out of, not the mileage on your vehicle. You'll need to get it reprogrammed which the dealer can do or there are independent shops that can do it too but they're kind of tough to find.

Section 13-01: Instrument Cluster—Conventional 1995 Thunderbird, Cougar Workshop Manual REMOVAL AND INSTALLATION Instrument Cluster Removal and Installation

1. Disconnect battery ground cable (14301) .

1. Remove screws holding instrument panel reinforcement (017A28) .

1. Remove screws holding instrument panel lower shield (045G02) .

1. Remove fasteners holding steering wheel column as outlined in Section 11-04 . Gently lower steering column.

1. Remove fasteners holding the instrument panel finish panel (044D70) and gently pry off.
   
   
   
   

1. Remove four instrument cluster retaining screws. (Do not remove screws from the instrument cluster main lens (10887) and instrument cluster mask (10890) ).

1. Slide the instrument cluster (10849) to the right of the instrument panel opening and unhook the instrument panel harness from the back of the instrument cluster .

1. Remove the instrument cluster from the instrument panel (04320) .

-----------------------
Speedometer/Odometer Federal law requires that the odometer in any replacement speedometer (17255) must register the same mileage as that registered in the removed speedometer . Since the speedometer mileage cannot be reset on this unit, affix odometer sticker to driver's door pillar and record original vehicle mileage. Removal

1. Disconnect battery ground cable (14301) .

1. Remove the instrument cluster (10849) as outlined.

1. Remove seven screws retaining the instrument cluster mask (10890) and instrument cluster main lens (10887) .

1. Remove speedometer assembly.

Installation

1. Position the speedometer assembly to the instrument cluster back plate (10848) and install.

1. Position the instrument cluster mask and instrument cluster main lens to the instrument cluster back plate and install the seven retaining screws.

1. Install the instrument cluster as outlined.

1. Connect battery ground cable and check the operation of the speedometer .

please rate if this helps

Check VSS Vehicule Speed Sensor wire may be corroted, bad connection or faulty; if 2wd the adaptor is located on the extension housing of the transmission (left side)
if 4wd look on transfer case extension (left side)

Good luck