In case this helps??? I dont know how similar the SC and GS models are, but thought I would post this in case it helps someone?! I just had to remove the automatic shift knob in my 94 Lexus GS300 so to remove the shift plate and ash tray so to replace the temperature control unit in the dash (the digital temperature numbers stopped working so I bought a used one off ebay from a junk yard, I got lucky, it works great). I stumbled upon shift knob removal instructions under the UK Lexus owners club. I had to grab the rectangular plastic housing around the base of the leather shifter, pull it down (it comes down fairly easy), revealing two screws. Once I removed the 2 screws, the shifting knob pulled off with ease. I then removed the ash tray (prying out on both sides with a screwdriver). After that the shifter plate came out fairly easy (then had to disconnect the wires)(upon replacing, after some struggle, I found that replacing the shift plate first to put the 2 end tabs in their proper place, then the ash tray works best). The ash tray hides the 3 bottom bolts (10mm) (I used 1/4in rachet and extra long extension) keeping the radio and temp control unit in place. After removing the air vents above the temp control unit (it pops out by prying with a screwdriver on both sides) and disconnecting the wires, you can remove the 2 top hidden bolts. Once the top and bottom bolts are removed, it slides right out, then disconnect the wires. It took me about 1.5 hrs to remove, replace, reconnect, and put everything back. No, I dont do this regularly, I watched videos and read what I could before starting which helped a lot. Good luck.