Thanks
She ran fine for about 10 mins just idling very well as sat for years. The dizzy has good cap and has not been moved and even kinda stuck in place by grim lol but will check timing.
My carby needs a kit regardless so will sort that and see.
When i google search about backfiring almost all results talk about carby fueling issues (this would also explain flat spot) as backfiring very uncommon in modern efi cars etc so might start there and also get some new ignition bits anyway as truck very old.
Replies may take a while as have to mail order parts where i live
J
