Thanks Marvin, to all intensive purposes I think that the caliper bolts turned out close enough. There was heaps of meat left for me to go where I wanted to. NCR used hollow steel by the looks of it, which is a bit risky for the road worthy certificate side of things, these Ti ones will do just fine. The originals have 4mm holes, but I used 3mm as Ti tears if your tightening the lock wire too much.
I used a 3mm cobalt drill which snapped 4 times (had a little stub in the end) the curing tip angle need to be more acute than the standard to get a constant swarf tail.
All in all thank you for taking the time and effort, very much appreciated.
