The 1991 Mercury Capri is essentially a rebadged Ford Escort. Therefore,
Ford Escort parts from the same years (roughly 1989-1992) will be the most compatible. You might even find some parts interchangeable with slightly earlier or later Escorts, but the fitment will be less guaranteed.
When looking for parts, specify the engine size (e.g., 1.9L or 2.0L) and transmission type as well, as those can vary compatibility.
