Water tank error persists after reed sensor replacement, float freeing

I am refurbishing a Jura Impressa E65 coffee machine. After a complete brew group rebuild and a pump / membrane regulator replacement, the machine functions well — but only when the outer cover panels are removed. As soon as the panels are replaced I get a water tank fill error.

It seems to be due to the fact the magnetic float in the water tank is too far from the sensor with the panels in place. I have descaled the water tank and ensured that the float moves freely. Thinking the reed sensor was the issue, I replaced it with a new one, yet the problem persists. I have also verified that the panels are correctly installed, and I even mounted the reed sensor with a shim behind it to ensure that the sensor is flush against the mounting tabs and as close to the tank magnet as possible.

Anyone have a similar experience or any ideas on how to fix this correctly? I am at a loss and am ready to “hack” the system by simply gluing the reed sensor to the removable panel, or even removing material from the panel so that the sensor can be mounted flush against the water tank.

Thanks!

Kevin