Pulled the 02 5-spd, yesterday, put in new gears today. The Redline had turned to a blue/green gritty paste on nearly all gears and had begun to plug up the oiling holes. We had the use of an industrial parts cleaner that heats to nearly 200 degrees but it still didn't get some of the crap off. Rags, brake clean, and elbow grease. I will never, ever, again use anything but a standard synthetic transmission fluid. Lucky for me, we cracked the case and were able to clean everything inside before there was any real drama. The only casualties were the two bearings on the final shaft. The races were pitted and scarred, and the needle bearings were discolored (the green sludge had plugged up their ability to oil).
On the plus side, I now have a stock 02 WRX 5-spd input shaft and 1-4 gears, including the H gear for sale. All are in excellent to very good condition.