borderdogs,
There is a good description of what I think you are looking for on the website americanlongrifles.com under Gun Making/Tool Making/Modifying a Versa-Vise by Jerry Crawford. The Versa-Vises are pretty hard to come by except on eBay and then they are pricey. Several of us on this forum have taken the Woodcraft vise referenced above and modified it like Jerry did and this gives you a very versatile vise with rotation in all three axis as well as a swivel jaw for holding odd shaped items without parallel sides. I have two that I modified and a local machine shop did most of the machining for me and they work great. One caution, as far as I know, all these vises are made overseas and ar not cast out of very hard metal. They will work for most of our gun building tasks but not for heavy pounding on with metals. You need a good machinist vise for that. Hope this helps.
elkhorne