Assembly is straight forward but:

1. Make sure to use a 2oz cu PCB.  The high current paths on the AC side are generouse and include traces on both sides but 2oz is required to keep temperatures down.
2. Use 16AWG stranded copper cords if possible.  Check drill hole diameter if you do.  I've used 18AWG and have gotten away with it running a 1300 watt space heater but the plug gets hot - like 50C.  Measured case temp is around 35C.  Note, the internal temperature sense is set to trip at 100C.
3. Making the flyback inductor is easy..  What's most important is the winding polarity.  For ease of winding & handling I use 26AWG although there's no penalty for 28AWG or even 30AWG on the secondary; it just gets fragile.  I use MW35-C HY magnet wire.
   
   1. Primary:  Np=6.  Start winding to right side (wire pointed away from body) with wire coming out bottom of core.
   2. Secondary:  Ns=17.  Start winding to right side (wire pointed away from body) with wire coming out bottom of core.  Start same side as primary termination.  Wind each side secondary half-way around core.
   3. Both windings should be evenly spaced around the entire core to minimize leakage inductance.
   4. Here's a picture of the completed primary:

   5. And with the secondary (primary @ top of pic, secondary @ bottom).  Note that the top right wire (primary) is on top and the bottom right wire (secondary) is coming out the bottom of the core) - that is the correct polarity.
      

   6. Don't worry if the loops are a bit loose like those in the picture or the spacing isn't perfect.  The ferrite core has a relatively high permeability and is forgiving in that respect.  Be sure the wire isn't nicked and test for shorts when done.