Here you go!
The white part goes into one part of the thigh the orange into the other.
Plug them into each other when dry and they will swivel but still have enough friction to hold the leg solidly in place.
I'd probably melt a paperclip or steel rod through each end to keep it from rotating inside the thigh (help give the JB Weld something to grip). Just run it perpindicular to the length of the pen.
(NOTE: THE CUT ON THE LEG HAS TO BE FROM FRONT TO REAR, BOTTOM TO TOP. THE ANGLE SHOULD BE LOWER IN FRONT THAN ON TOP. REVERSE THE YELLOW LINE AS SHOWN IN THE PICTURE BELOW. ALSO POSITION THE BIC PEN PARTS PARALLEL THE CUT).