Can swap the part of the dash with the light & emergency blinker switches so it fit. Also have to swap circut panels on the back of the clusters along with the tach's for it to work properly and so that the tach reads correctly.
Had to do this in an 87 coupe when we swapped a newer style black interior on a 4 to 8 EFI conversion.. We put all the dash items in the car, but kept teh 87 wiring and swapped the plastic circut board on the clusters to make it work.
That's a big NEGATIVE.... over! I just fiqured out today why my tach was running so high, about 2x what was actual rpm. I had a 6k tach 4cy cluster. Which I found out anytime you have a 4cy tach in a v8. Your tach will be off big time a couple grand. As I was explained by my ford tech buddy who brought in a digital tach and discovered this. The 4cy tach reads twice the rpm because your v8 is sending 2x the sparks. Your tach cluster can not distinquish the difference. It will just assume you have a 4cy that is revving into higher rpms, which is not true. I believe the early 80's tachs (which you wouldn't be able to use anyways) did have a 4/6/8cy switch so you could change it. But looks like you'll have to buy a v8 cluster. Btw if it's unclear 87-89 will not work with 90-93 due to airbags, wiring connectors (unless you repin) and because the depth at which the cluster sits inside your dash... guess you could call it "depth set" will not fit. If you're looking for a 140mph 7k tach, you need one specifically pulled from a 89 gt/lx/nb v8.