Richard,
Are you asking how QS and ISO differ in general, or how Ford applies QS as opposed to ISO to their supplier base?
If the latter, Ford doesn't "require" either QS or ISO from their suppliers. (QS-9000 3rd Edition pages 67-69)
What they to require is implementation of the Ford QOS methodology which in my opinion a good process.
Will they accept QS and ISO registration? Well, it doesn't hurt.
I don't have my TS manual with me so I will hold back on that comment.
I have minimal hands-on involvement with Ford, so let's here from some members with Ford experience, I've been wrong before and will be wrong in the future!
Update: By the way, consider G.M. for your project, they are more aggresive with, and do require QS-9000 as a Quality System minimum. Also, QS is nothing but ISO plus automotive requirements. Do some searches on this site and you will find alot of good information.
ASD...
[This message has been edited by Al Dyer (edited 02 April 2001).]