If you're buying a car for a swap, you might consider a base 88 coupe. Other than the engine and trans, there really is very little difference between it and a Formula, except for the absence of a rear sway bar, and the instrumentation. Both are easily remedied.
I bought an 88 coupe for a swap. My only requirements were: No rust. Reasonable cosmetics. A factory 5 speed trans, and factory A/C.
It leaked oil so badly, I nicknamed it the Fiero Valdez.
Once I rebuilt/upgraded the suspension, and fixed all the oil leaks, it has become quite the reliable driver. Runs so good that I'm not in any hurry to snatch out the Duke.