Hi Austin ( Warbird ) ,
At the recent open day at Oakmere , chatting with the M3W service engineer about getting parts blackened he recommended a local firm who specialises in this :
http://www.wilkinsonspowdercoating.co.uk/contact-us.php I am considering getting my heat shields power coated ( so I dont have to keep polishing them ! ) . I have not contacted them yet , so no opinion on service.
Might be worth getting a quote ?
GRaham