Will a 1991 Geo Metro engine fit in 1996 Metro?

While both are Geo Metros, there's no guarantee a 1991 engine will fit a 1996 model without issues. There might be minor differences in mounting points, wiring harnesses, or even the engine block itself between the model years. While many parts are likely interchangeable, it's not a sure thing. You'd need to carefully compare engine specifications and mounting points to be certain. It's best to consult a repair manual specific to both years for a definitive answer.