That is not a 1993 engine, it more resembles the carb version of the 4G63 engine, and you will be pretty sorry to hear this. Your transmission will never work correctly with this (if its the GDI one) because you are missing the crank sensor input, Throttle Position Sensor input, Air Flow Meter input and Engine Coolant Temperature input.
All these are shared by the TCU to set the shift timing, shift aggression, converter lockup, and kickdown too. I also see a blue filter on the transmission which is not OE, the only filter to be ever used is the OE mitsubishi part - the recommended ATF diaqueen 3 is dexron 3 equivalent. But that is irrelevant now, because you are missing input signals to the TCU (transmission control unit)
I have done several swaps of these cars, usually with 4G63 NA, 6A12 and 6A13, the wiring is quite a lot but once you understand the mitsubishi design its very simple and modular. If this were my car I would either convert it to manual gearbox or buy a proper EFI engine for this. And for anyone else reading this thread, When I refer to the hybrid car future in Pakistan, this is a class example.
The original 4G93 GDI engine this car utilized has unbelievable low end torque and excellent economy, Uptil the time it works, once it goes bad extreme expenses are required to bring it back to serviceable specs. Most cars then suffer this fate - as proper engine swaps for this car racked upto Rs 250,000/- in 2005. (that included everything worked like it should including HVAC, SRS, security, keyless etc.) I believe it would be double that in todays price.
The last galant's sold by Dewan motors had a carburettor 4G63 NA engine with full electronic automatic gearbox, that TCU took signal from the speedometer, rpm from coils, throttle position sensor from the carburettor and its own dedicated temperature sensor on the engine. Try to find that TCU and all its required bits.