There's a lot of instruction floating around and I just thought this one might also be useful and helpful for those who are visual learners. Kudos for Little_Buster for providing the instruction.
If you have tried this mod, let us know what you think of the new sound or the drop in volume.
Step 1: C4 Mod Materials
(1) Bowl or cup (you don't want to lose any screws)
(1) Pair of small scissors, wire cutters, or nail-clippers.
Step 2: Removing the C4
2. Unscrew the bottom 4 screws from the pedal, and put them in your cup or bowl.
3. Take the bottom panel and plastic covering off underneath that.
4. Pull out the circuit board, keeping in mind you will have to pull out at an angle so the 9v adapter box can slide out of its hole with ease.
5. Locate the larger of 2 small "silvery pillow" objects (capacitators, if you know what they look like) and cut/clip both leads from the circuit board.
6. Tape the C4 inside your pedal somewhere so that you don't lose it. ( In case you decide that you hate a good sounding pedal, you can solder it back in.
7. Put the circuit board back in, replace the plastic cover, screw the bottom panel back in, and you're done!
Step 3: Changing the LED
2. Unscrew the little board that holds it.
3. Desolder the LED.
4. Solder in the NEW LED.
5. Mount the little board and screw.
You are done!