The manifold is mild steel.

The white connections are earths. It's an EDIS8 ignition running of a trigger wheel in the dizzy. The EDIS coils are different to most in that the high tension side has each end connected to a plug. Most coils one end is earthed. I wasn't sure how closely the inductance had to match the stock setup so I used the stock coils for now. Later I'll look for something a bit more compact that I can mount somewhere else.