This is a few ideas Jim..
The first was my test spinner. I then did it on a purple anodized spinner. It works good as far as I can tell.
The second I pulled off someones site at some point.

Now, I have had the idea of having a spinner the has the bolt in the regular spot, the having an area behind it for 1/4" being finned to direct air in. I may still do it at some point. Just haven't done it yet.

My setup is with the Axi.

Chris