On my Norco Optic the shock mounting bolts are M6x1.0 and the torque spec is 8 Nm. The hardware to attach the link arm to the frame is M8x1.25 and the torque spec is 10Nm.
if your hardware is actually M8 thread and you don’t want to wait for a spec, I’d just do 9Nm and call it good. Also likely want some blue 242 Loctite on there.