I’ve seen some people on Reddit hook up bass shakers to a wireless subwoofer, but they always feed the wires from the driver through the port. I wanted it to look a little cleaner. I soldered some wires onto the subwoofer driver directly and hooked them up to a terminal screwed to the back of the amp. I then designed and printed a case for the terminal and the speaker to line level input converter. I used magnets to secure a cover to the case.

Russound ADP-1.2 Speaker-level to Line-level Adapter: https://a.co/d/0en8yutI

2 Way Spring Speaker Terminal Clip: https://a.co/d/09Rr2GBC

6x3mm Magnets: https://a.co/d/0j0xO189

For my bass shaker setup, I'm using the following:

Fosi Audio TP-02 Subwoofer Amplifier: https://a.co/d/01tvsO0b

24V 10A Power Supply (for more power): https://a.co/d/06zbQFNq

Dayton Audio BST-300EX Bass shakers: https://a.co/d/08vQzoPs