This one is a single PCB, partially-prebuilt project with a few strategic bits left open for through-hole parts. The BOM is:
Build order could not be simpler: diodes first, then all transistors/capacitors, then flip it over and do the trimpot and power header on the back side. Next, install the switch and solder one or two pins to tack it down. Be sure it's flat to the PCB - fortunately, the side clips do a good job of keeping it snug. (But be sure.)Capacitors
 1.2uF Tantalum
 10uF Electrolytic (Lay flat if too tall.)
 1uF Polyester (large off-white cap in photo)
 0.1uF Polyester (as marked in photo)
 2200pF Polypropylene (red caps in photo)
Transistors/Diodes (marked in photo)
 NPN - Two matched pairs. Choose your own, but mind the pinouts.
 Diode - 1N4148 or similar
 200R Trimpot (backside) - CV Reject
 10P Header (backside)
I/O & Panel Controls
 3-pos. rotary switch (Mouser #688-SRBV131502 or #688-SRBV131803)
 Inline/Thonkiconn jacks
 12.5mm knob ("Mini Fluted Knob" @ Erthenvar [1900 clone] or similar)
 19mm knob ("Medium Fluted Knob" @ Erthenvar, or similar)
 25mm knob ("Large Fluted MXR Style" @ Smallbear, or similar)
 Pots - Alpha 9mm Vertical or similar
- 1x B100k
Then pop in the jacks and pots, lower the panel onto the unsoldered components, and snug up the washers/nuts. (Don't forget to peel the protective film from the panel first.) Lastly, flip it over and solder everything in place.
I like to leave the spacing tab on the switch and just install the nut finger-tight. Works just fine. You can build it up flush with the back side of the panel using washers/spare nuts though, if you prefer.
Trimpot is for CV rejection, which this filter does reasonably well. Leave the audio input empty, plug a VCO into one of the CV inputs, turn it fully CW, and trim until you get the lowest level you can manage at the output.