Thanks Dave, all the info is greatly appreciated.
The photo of the mounts you posted is good enough of me to go on. If you could please give me the wall thickness of the "pyrimids" plates if you have it on hand. I assume the round part of the mounting is solid stock, turned down to the right dimension and the correct size hole drilled through. I have a lathe so this should be no problem.
From the photo, i can see the "pyrimid base" is welded together but is the round bit welded or brazed into place. Why i ask is the "welding" around the top looks very "smooth" as if it was brazed.
I assume i'll have to use 4130 to build the mounts, not ideal to have the engine part company, could ruin a perfectly good day
May i say, all three Nipper owners in SA are members here and i'm sure are finding all the info you guys are supplying, very useful, Thanks once again
Chat latter
Glen