I had posed a couple questions about the MKC last week.  Well, I just assembled mine this weekend, and can I please tell you… I am Freakin THRILLED!    This is the sound I have been searching for.  My concerns about the omission of the original boost power supply, and the possible sonic benefit have been put to rest.. This is the best pedal I have built or heard. Bar none. I tweaked your tweak a bit for R15… Instead of a switch, I added a 50kLin pot instead.  So I can adjust the drive somewhat infinitely. I have single coil, P90 and Humbucker guitars across multiple amps, so I think this adds versatility and removes the guesswork.  What a great job, and re-interpretation of this circuit.  Thank You very much!   Please excuse the rough labelling, I was in a rush to get the pedal up and running, and anxious to hear it!  I plan to re-do the labeling soon.  But, its whats inside that matters.  Barry has nailed this one.  This pcb gives you many options, and all the scrumptious Klon-nes that I loved on the reviews and demos of other pedals.  With the Fat switch engaged it really sounds better, more pleasing, yet more forceful and open than any of the videos I watched for other klones.  I am just running straight 9volts so far. For my diode choice I ran a pair of 1N5817 schottky’s with a 170ohm resistor inline with each… very sweet.  I cant make this pedal sound harsh or brittle anywhere.  So happy!