The idea is simple enough, but this is a short writeup for those who have never changed their manual transmission fluid on the SC300. **NOTE** You CANNOT fill the transmission through the shift hole from inside because the SC300 has an extension on the transmission that brings it back.
15/16 wrench or 23mm
15/16 socket or 23mm
Ratchet to match
Funnel with long narrow end
Washer for drain plug and fill plug
2 different sizes of fuel line (One that fits over funnel end and one that fits inside of previous line)
3 quarts of GM Synchromesh (or whatever floats your boat)
1. Jack the car up and put on jack stands. Don't forget to chalk the rear wheels with a piece of wood, etc.
2. Whatever you do, for the love of god, loosen the fill bolt first before draining. Use the 23mm or 15/16 wrench (I used a 15/16 because that's what was close and it fit)
3. Drain the fluid into a drain pan and tighten bolt back into place. Replace the washer if necessary.
4. Assemble your funnel/fuel line ghetto transmission filler and run the "filling lines" by the clutch slave cylinder for the shortest route possible.
5. Fill with new fluid. The specs call for 2.7 quarts to fill, but I dumped in all three.
6. Tighten fill plug.
7. Lower car off of jack stands.
8. Enjoy the the newfound buttery smoothness of your shifter.
I hope this helps someone.