Requested by a few people. The juvenile in me was so tempted to call this one the Huge Pork Sword, but thought I should start acting my age :o)
This is a fairly big circuit for an overdrive but should still fit in a 125B I reckon. It seems to be very tweakable with 5 external pots and 3 internal trimmers so should give a wide range of tones.
The 2N2484 transistors aren't very common but can still be obtained from a few sellers on eBay without re-mortgaging your house, but if you don't want to buy anything in specially, just use any NPN transistors around 250 - 400 hfe. The 2N2484's are metal can with the triangle pin arrangement allowing you to easily mount in any pin order, and you'll notice that to make the layout flow better Q4 and Q7 have an unusual CEB pin arrangement. Keep that in mind when selecting and mounting the transistors, and twist the pins as required if using a transistor with inline pins.
Info about Jeorge's, and now Dunlop's, versatile overdrive pedal:
Make room for one more Way Huge original! The Pork Loin incorporates two distinct tonal pathways that are blended together—a modern soft clipping overdrive and a modified classic British preamp for clean. At the heart of the Pork Loin’s overdrive path is a soft clipped BiFET overdrive gain stage with a passive Tone control, rounded out by a Curve function that gives the user freedom to fine-tune corner frequencies. The Volume control regulates the masses of pork power that exude from its space age circuitry, leaving room for the Clean control to blend in its warm glistening clean tones. Additionally, the Pork Loin has three internal mini controls: Filter and Voice deliver extensive tonal shaping possibilities, while the overdrive Mix control allows the Pork Loin to be run as a clean preamp. With a wide range of dynamic tones, the Pork Loin is the premier overdrive pedal on the market today!