Dont worry rob i really do appreciate your pointers as you have been building these things for years and have great results, clearly shows ur a wealth of knowledge.
U prolly didnt see my post just before, but im using a convential cap head bolt, not a tapered bolt. I can see the issues ud have if u used a tapered head bolt though.
Yeh i was going to wait and test it on my own car but its getting some chassis work done atm so it wont be ready to use for sometime, also i'm working with a workshop who have cars available to test on and if testing goes to plan a drag car to test on half way through the year.
I do see issues already like how are we going to overcome differences in thermal expansion (most likely by running non-std clearances), line boring with the 2 different metals and many more, but like u said thats what the testing is there for!
Thanks for the help so far, i really do appreciate it