Thanks Peter for the feedback on copper washers.
Those Goodridge seals do look nice and thick. The originals I used were the ones that came with my Goodridge SS braided hoses but I don't think they were as thick as those.
Even though I have now refitted the hoses again with two soft cooper seals (supplied by HEL Performance) I'm now thinking that this is the wrong approach on these calipers. The area around the threaded hole has not been machined flat and is just the rough casting finish suggesting the seal should at the bottom of hole. But the Goodridge hose fitting is the wrong shape to seal with the concave seat in the caliper and being Stainless Steel it doesn't deform when tightened up.
Looking back at my dismantling photos I can see the original builder used traditional rubber brake hoses which were simply screwed into the caliper without a copper crush washer.
Front brakes, hubs, etc by
Sabrebuilder, on Flickr
EDIT: This is the wrong photo, please see post #408 below
A bit of a retrograde step but i'm thinking of reverting back to rubber hoses.
