After two unsuccessful attempts at making a cross member on my part (bad measurements and impatience) I decided the better tool in the tool box was the check book.  After checking products across a few sites and not seeing what I was looking  for, I called Snow White and asked what they had that might fit my application ('59 Chevy).  They have a universal cross member for the JAG IRS which is 36 inches wide and comes with an isolation mount and adjustable width shock mounts.  Cost with shipping (through UPS) is about $350.
The isolation mount for the center seems to be set at a six degree angle.



Moral of my experience, if you don't see what you're looking for, call and ask.  Not all products (yet) are on individual web sites.  Also, shops have info and still like to talk with potential customers as time allows.

Universal Cross Member from Snow White:

Underside showing adjustment on shock mounts:

Last edited by 303Radar (8/16/2012 8:55 pm)