One of the most popular questions we get is, "Can I swap out instrument clusters in my 1985-88 Cougar/T-Bird?" Well, the answer is "yes" but it's not a straightforward, plug-and-play situation. Unlike cars of today, there wasn't really a lot of foresight when planning the wiring harnesses on these cars. Then again, there were a LOT of options and trim levels available, so it was never likely that anything would be engineered for a swap in the first place. That doesn't mean it can't be done, though.
There were three types of instrument clusters for these cars from 1985-88: the base (standard), full electronic, and analog. Of these, the analog seems to be the most desirable because it displays full instrumentation very easily. A lot of people like the full electronic cluster as well, but it's a long and arduous trek to install one of those into a car. Most people seem to want to step up from the base to the analog, or from the full electronic to the analog.
So how exactly is the swap done? In a nutshell, once your existing cluster is loosened, you will have at least one wiring harness attached to it (the base and full electronic have two). Whichever stock-style cluster you're installing will require different wiring. This means you will need to rearrange the wires inside the harnesses to work correctly with the new cluster. This is known as repinning and it's not really that difficult to do. After that is done, the new cluster can be installed and tried out.
Of course, there are a few caveats to this swap. For instance, analog gauges use different sending units so those would likely need swapped out (and that could include the fuel sender in the tank). You may lose your the shift indicator in the new cluster. You may have to run some new wires to pick up the tachometer signal. The tachometer may need additional calibration in order to work correctly (see this page for more details). So be prepared for some extra work if you're going to do this.
We have prepared several conversion guides to help you do the conversion—see the download links below. Also, we have provided the wiring specifications for all three harnesses here for your convenience.
For an instruction manual on swapping from the base to the analog cluster, download the PDF file here:
For an instruction manual on swapping from the full electronic to the analog cluster, download the PDF file here: