stigs2cousin
Premium
The idea is either to move the plywood plate directly to the seat spring or cutting 2 smaller pieces and boltthe pucks on then squeeze them in
Maybe start a trial run by ziptying the shakers to the springs.
My "trial run" with BST-2 ziptied to the brake pedal lasted well over a year before I fabricated a mount.
As you said might not be super comfy so the other option iam thinking would be to bolt the pucks on each side of the silver seat frame you see in the picture
Still not convinced the Pucks (and Nobsounds) have the power to shake the whole seat from the mounting plates. (also a lot of energy will be "wasted" into the rest of the rig)
But, by all means try it out, all you have to loose is some time tinkering
(and some obsolete holes in the seat mount)