Gaz,
I have just set the intake manifold gaskets in place and need to let them cure before trimming the excess and starting the reassemble procedure. I have switched 2 of the carburetors to see if the issue travels or stays with the cylinders involved.
I currently have a 100 idle jet holder with a 70 jet and the primary is a F11 with a 170 jet.
Here are a few pics of the linkage.
