M.O.R.E. MM and Bolt size

I just installed my new MORE MM and picked up a couple 1/2"x5.5" bolts since I seem to have lost my stock bolts. The 1/2" bolt fits the block side mount perfectly, but won't fit in the MORE mount. So do I try to drill out the hardened steel MORE mount to 1/2", or just go to 7/16" bolts that will have a small gap between the bolt and the block mount?

Thanks!

I used the stock bolts when I put in my M.O.R.E. mounts. IIRC, they're metric. Try an M12 bolt. Don't remember what hardness, though.

M12 fits the MORE mount perfectly. Now if I could only find an m12 bolt long enough locally...