Hi Lee
Thanks for that - I've saved the diagram, and will have a look at it some day. It wasn't right after having had the coils done by Skip Haney - better than it was, not still not right.
We hadn't looked at the wiring much, but had kind of stalled out on something else I'd read either here or somewhere else - that all the plug wires jammed into the two tubes that run down each bank could age and start leaking "spark" amongst themselves and to the tube, so had kind of stalled out on the idea of replacing all those wires in the tubes to see if that helped.
But using that diagram to check things out would also be helpful. The car had been part of the "Ride the Classics" programme - it's not good enough to be a museum car, so for some time has sat in one of the storage barns.
Again thanks
Roger