MustangForums.com - different guages and dash???

I am here to advise you against attempting this. I had an 85 that I robbed a ton of parts for from an 89. While the seats, rear interior panels, quarter windows, front and rear bumpers, and door panels are a direct swap out, the dash and console are a totally different matter. I almost completed mine, but the e-brakes are totally different. The 87 and newer uses an offset handle, while the 86 and older have a direct handle. Unless you want to cut a hole in the floor of car and build some sort of mounting bracket, you will not be able to mount the console correctly. Any time I want to set me e-brake, the backside of the console had to be lifted to allow this. Since it lifts up, you cannot properly fasten the console down.
The dash will fit in place, though not on the original brackets. I picked up some self tapping sheet metal scres at Lowes and directly attached the dash to the rail that runs under the windshield. The connectors going into the back of the cluster are the same, though the wiring is different. You will need to get a wiring diagram for both complete dashboards and compare the two, then re-wire the harness.

Like I said, I strongly advise against this unless you are some kind of super tech. I was working as a painter at the local Ford dealership and contracted a mechanic to help with the swap. We worked the entire weekend and were frustrated as hell. In the end, we did get everything alleviated other than the e-brake so it is possible.

by the way, mine was a 5-speed so the e-brake was essential. If you have an automatic, the e-brake may make no difference to you.

I do understand the 87 and newer dash looks much better, but in the end, it's just not worth it.

If you can find the 87 rear quarter windows, they are a direct bolt in. You have to remove the current windows and ridiculous looking sail panels. When you do that, pick up the rear interior pieces too. They have really cool speaker mounting locations.