Emperor 400 Power Unit Removal?

Has anyone successfully removed/reinstalled the power unit on an Emperor 400 HOB filter?

I realize it is not designed to be removed, just wondered if it could be done. I have a severely limed up filter box and I'd love to soak it in some acid for a day or so vs scrubbing with a toothbrush.

The power unit looks like it is epoxied in there, but I wasn't sure. Got it mostly cleaned with lots of scrubbing and muriatic acid. I Don't think I have a bucket big enough to soak it in anyway...

Probably would have been more efficient to buy a new one, as cheap as they are now.

It's running now in a tank with dilute muratic acid...to finish cleaning the filter, tank glass and glass tops (which are soaking). Will check it all tomorrow