What I ended up doing, was buying some regular hex nuts and just had a buddy of mine machine the neck on to them.  They are not welded on, but worked pretty well.  I still have the same ol "56' hood issues", but it is definitely better than it was. 

HI there
 
I've got the hood (bonnet over here) off of my 56 at the moment and one of those nuts has broken free.  I think they are shouldered weld nuts .  They com with tiny projections on the corners and are fitted with some kind spot welder. I did a search on the  interweb  and they are available if you want to buy 100s.  I was thinking to drill 4 tiny holes to find the corners of the nut and tack with a tig welder. I you come up with a better idea please post.
Good luck
stuey
UK 

Try Mid Fifty.  http://www.midfifty.com/

Does anyone know what type of nut goes on the hood hinges, on the end of the shoulder bolt that holds the hood to the hinge?  I can't find anyone that sells them and regular nuts tighten up and put the hood in a bind.  I had one "original" (I think anyway) and it was square with a little neck on it where it would pivot with the hood.