Hot Rods Joe Hunt Distributor advance?

Let me start off by stating I wish I just used a Mopar performance or some other conventional distributor, but the money is already spent and I have to work with what I have.
I have a 392 Hemi with one of the Joe Hunt mag looking distributors and I'm having some issues related to timing. The problem is the distributor has to much advance built into it. Does anyone know how to shorten up the advance curve in one of these things? I need like 15 to 20 degrees and this thing has at least 30.
Thanks for any help you can give.

 

Did you call Joe Hunt, think they are still in business.

 

I had one of those with a similar problem. I sent it in to Joe Hunt and they fixed it.

 

I'm trying to avoid sending it out for repairs, else it it's not to difficult. Not then anything, I don't want to brake something dissembling the distributor. I have tried calling Joe Hunt, but there not open when I'm available to call.