Mounting Haptics to 8020 rig/seat

I have an ASR3 rig with the NRG bucket seat. Looking for how best to mount x2 Dayton BST-1 shakers to the rig. One for the road feel through the seat, the second through the pedals mainly for ABS.

Are there some good generic mounting options rather than having to buy the $150 ASR mounting bracket that the make for the bass shaker. I have heard it’s not great to drill direct into the fibreglass seat back/base.