I'll go out on a limb and suggest a set of allens made for a 3/8 drive ratchet wrench. This usually has enough oomph, if not can be used with an impact driver, and you can use a torque wrench to tighten the fastener to the correct spec. How do you do that with a "L" shaped allen?
Geoff

I never wanted to lead, and I never wanted to follow. I just wanted to ride.