Just finished mine lastnight. you have to get the harness and computer from a focus year between 00 and early 02. you can look at the plug in for computer and tell the difference between them the one you need is one big plug. that harness goes from the fuel pump all the way down passenger side of car to the engine bay. it goed under passenger seat to shifter so youll have to pull out center consoul. also you need the oxygen sensor/trans harness. plugs right into top of trany back side of trany, both o2 sensors, crank position sensor, and power steering pump. you need the high pressure power steering line that runs across top of exhaust manifold. throttle cable, cruise control cable if you have it. alternator power steering pump ac compressor the ac lines, passenger motor mount both peices,both heater core hoses (maybe just the one i cant remember, vacume lines that come out of the intake on backside, flex pipe for exhaust. Also tey and get the key to car you take computer from. zip tie it under steering columb next to lock cylinder and get a plain key cut of your old one. thats all i did and it works fine otherwise you gotta pay like 100 bucks for key reprogram, and an engine obviously, and NO you dont need the trany from the zetec they are 110% exactly the same i researched and i used my SPI trans with zetec with zero issues (BUT IT MUST BE AUTO TO AUTO SWAP IF YOU DO MANUAL TO AUTO YOU GOTTA CHANGE CRANK POSITION SENSORS, i think thats everyhing. its time consuming and you need more than basic car knowledge i didnt have much time so it took me month an a half doing it on a couple weekends when i had time.
Well I used my spi trany and have no problems and my cousin works at oriellys we looked them both up and part numbers are same ford says same thing. Maybe newer spi an zetecs are diff but mines an 01 and they are EXACTLY the same