Well I just got an email response from Proline Customer Support and this is what they e-mailed back to me when I asked them about what body is compatible with the Matrix TR Arena.

Quote from Proline Customer Support:
" The CEN team drivers we work with use the Crowd Pleazer for the Mugen MSR kit #3215-00 this appears to be the best fit."

I thought other Matrix drivers would like to know. But I also do love the CEN Matrix TR Arena clear cab. It does have a nice design to it.

~ Simply Unreal