Can you use the M3 strut brace on a non M3?

I have the M3 brace mounted but the bolts don't go all the way through the nuts on the stock strut mount. Maybe like 2/3 of the way. I tried to get the reinforcement plates in their as well but it was either the brace or the plates as they both wouldn't fit. Did I miss something with the hardware? Are there special nuts that I have to buy to make this work for a non M3? It's way too confusing. Some sites say it can fit any E46 and ECS is saying only M3. Which one is it?

Can you use the M3 strut brace on a non M3?