where-ever you find it, it's probably going to need to be rebuilt. saab switched to MHI and garrett t25 series turbos in the late eighties.
the ford 2.3L turbo was a t3. it was used on the following:
* 1979-1980 Ford Mustang, Mercury Capri (carbureted)
* 1980 Ford Fairmont, Mercury Zephyr (carbureted)
* 1985-1989 Merkur XR4Ti
* 1983-1986 Thunderbird Turbo Coupe
* 1984-1986 Mercury Cougar XR7
* 1983-1984 Mustang TurboGT (W Code)
* 1983-1984 Capri Turbo RS
With an intercooler:
* 1987-1988 Ford Thunderbird Turbo Coupe
* 1984-1986 Ford Mustang SVO