Loosen the bolts if needed, and install a required amount of shim plates, and tighten the bolts so, that the shim plates will be tightly squeezed. Final tightening torgue MAX 20NM. NB! DO NOT USE A BOLT MACHINE TO TIGHTEN UP THE BOLTS! Risk of over tightening the bolts, cracking of the plastic part or the bolts or a seizure of the bolts.