Wow. Great. It`s exactly what I have in mind for my setup (using the same chair as you...)
I plan to use 2x Dayton Audio BST-2, which come in at 35W max each.
Did plan to attach the Amp to the chair, but your solution seems to work better, when planning to deattach everything.
How do you like your 2 shakers? Do you think that`s it too much or do you feel it`s just perfect, mounted on your seat?
I`m asking, as your shakers would correspond to Dayton`s BST-1.
Did you also mount some transducers to your pedals?
I`m keen on trying that as well (most likely by using some small Dayton TT-25), plus maybe mounting a 5th small shaker to my stick.