Hi Madz,
I apologize that I'm not answering your actual question but I just converted an inexpensive Pearl hi-hat stand to be a Hall Effect pedal. It was so inexpensive and easy to construct that I'm suggesting you consider it. Several forum members have posted photos and answered questions. I'm putting together a step by step with parts purchased on Amazon's US website. It works very well with the MegaDrum.
1. Purchase terminal strip:
https://www.amazon.com/gp/product/B01CG2HI0E/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=12. Purchase A1302 Hall Effect Sensor:
https://www.amazon.com/gp/product/B07DWXCTFL/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=13. Purchase TRS cable
https://www.amazon.com/Hosa-MHE-310-Headphone-Adaptor-Cable/dp/B00BGDMIOG/ref=sr_1_3?keywords=TRS+cable+10+ft+1%2F4+to+female&qid=1566655099&s=industrial&sr=1-3-catcorr4. Pull magnet from dead hard drive
https://youtu.be/YKzPt18aE_05. Let magnet attach itself to the foot pedal (or build a mounting bracket for it)
6. Hold the sensor smaller side up with a needle nose pliers just above the little indents in the legs
7. Bend the outer legs at a 45 degree angle to the middle leg
7a. (Optional) - bend all three legs to 90 degree angle so the little square sensor is on same plane as the magnet
8. Unscrew the terminals enough to slide the legs in between the square metal washer and the terminal plate below it.
9. Tighten that side of the terminal strip
10. Cut off one end of TRS cable
11. Strip back the outer jacket
12. Untwist the copper shielding wires from each conductor and twist them together into one
13. Strip each conductor back enough to insert into terminal
14. The copper shielding (common) goes to the middle.
15. Figure out which conductor is Tip and which is Ring (red was ring and white was tip on the cable I used)
15. The Ring conductor goes to the left (looking down at terminal strip from side opposite where sensor is connected)
16. The Tip conductor goes to the right (looking down at terminal strip from side opposite where sensor is connected)
17. Position the terminal strip so when foot pedal is press all the way down the magnet is 1-2mm from sensor. For the hard drive magnet it worked best if the one tip of the flat side came down to be 1-2mm from the flat side of the sensor (I've been told it doesn't matter which side of the sensor)
18. Make sure right most switch on MegaDrum is up (Pedal impedance)
19. Press pedal down and look for white number next to purple LVL label to change on the MegaDrum Info page (default page when you switch on). Mine goes from 445 to 720 - the numbers don't matter as long as they are a spread of more than 127.
I should add some photos to this but just wanted to list this all out in one place. If someone sees an error please comment and I'll edit this.