Hello Ghost_51
Another restoration shop you may try is Gosshawk Unlimited in AZ, it has done restorations in P-51s and also maintains a few.
If I can be of any help in the UK then let me know. I own Vintage Warbird Restoration Limited and have some 30 years metalwork fabrication skills, working on various warbirds from B-17's, P-51's, Spitfires, FW-190's, P-40's etc. I have a small workshop but can do most of what is needed to restore warbirds, at the moment I'm doing a Mk V Spitfire, so it would be good to have a change and do some work on a P-51.
Regards, Spitfire Steve