i used alen key headed bolts roughly 30mm long with locking bolts. i have just used 3 fixings either side as the one on the inner side was not possible to get to.
all i did was popped the bolt through the 3 holes that i pilot drilled first, jacked the car up slightly and held the nut with a pair of plyers and tightened up, bit awquard to do but doesent take to long! oh and as for the one i missed out i just glued in place.