I killed a saitec st 290 pro  .. for the main controller board , 8 way hat , lower buttons  . then put all that into a mad catz panther  joystick  . 
the potentiomiters are far superior in the panther so i used those . 
for the rudder peds i used  a pot from a old tm stick and connected it to the saitec board 's previous (twisty)  rudder connection  .. using an old game port plug  (the panther stick used a game port plug previously  for the rudder connect .
 i placed a disc on the pot then made a sloted bar that connects to the peddle main tube  as for it was too sensitive and needed some built in freeplay . I added 2 more springs to the disc to hold it to an auto center . 
the foot pads rotate about 30 deg's total because i sloted and added a post for a stop .  
So far i have no spiking  ... but i do get and off calibration every once and a while in the peddles   ,I'm thinking twin pots in series may be the ticket here . I have another set of peddles that work this way and they were rock solid  cal wise .. but there action  is very hard to do comfortly . (they are sitting on top of the toolbox )
So these are my 1st set i made .. just a tinker project after work .. 
( yes i bend,weld,beat up metal all the time )
I'll make another set soon but with lots of improvements .
 a  bearing instead of bushing in the center pivot for starters.
Design brakes , along with the main springs hidden underneath . 
Then make adjustable spring rates, main stops, ped angles.
for interface it programs the same as a saitec  and connects usb .
i had to make schematics for bolth sticks by hand and ohmmeter .. (Yes i wrote to bolth manufacturers and searched the net for weeks for them)