I have a Pochon counter too which does not work but it seems to have a working LCD screen. Is there a chance I could have your old counter to test if I can make a working unit from both units. It's a long shot but if it works I would be happy to compensate you for the part.
If it does not I am very interested in learning how you installed your new counter.
You can e-mail me directly at josegvenega-at-icloud.com