Buttkicker gamer plus placement HELP

[pnkdngnrcr]

I have this buttkicker mounted via two bolts to this cross beam that is connected to the two rails (running perpendicular to the beam the buttkicker is on) which are the rails that my NRG prisma seat is attache to.

Im finding the feedback to be a bit weak. Do I bite the bullet and mount this to the seat (drilling through the fiberglass), or can somebody suggest another way to do this with limited additional fabrication?

 

[Junkie]

Try mounting it to the same bar your set goes on if possible.