The input spool on the 3000GT / Stealth AWD Getrag transmission/transfer case setup (W5MG1 / W6MG1) is very prone to corrosion and spline wear. Anytime the transfer case is removed the splines should be cleaned and have heavy grease applied to both the shaft coming out of the transmission (output shaft) and the splines inside the t-case, the spool as we call it.
For those that do not work on these units often it may be unclear what to press on and off, so we have produced a video showing this. Please note you NEED a 40 ton press or larger to do this SAFELY. Do not be tempted to use a small 20 ton imported unit as they can actually bend and cause injury or property damage.
Please note the transfer cases on these cars are basically small rear ends and need to have their bearing pre-load reset anytime components are replaced. New spools can be tighter or looser and require adjusting the shim underneath the bearing race nearest the seal that faces the transmission. They also need the backlash and pinion depth verified or you may have clunking, whining, or other issues.