Should be a direct bolt in. Keep your torque converter and flex plate (unless your old trans failed - you'll want the TC inspected OR get a known good unit to swap in). Be sure to re-use your speedometer gear as well.
I don't know your circumstances, but if you are going through the effort to replace the trans and have the ability, get something 01 or newer, all the recommended modifications to the valve body and case were made by then to greatly improve the power handling performance and longevity of the transmission. If you do, don't go newer than 03 unless you swap the output shaft; after that they use a different type of sensor that won't work with your car. You'll also need to re-use your MLPS, TCC solenoid as well as rerepin the harness.
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