When I was having problems with my slant I wish I would have just started by verifying everything was at the correct 'settings' instead of trying to diagnose why it wouldn't keep running. It would have saved me days of frustration. I see you have replaced a bunch of things but have you verified that they are all correctly working? points gap? Old Fuel? Vacuum leak(s)? Valve lash? Distributor advance degrees? Whats your vacuum reading? Float height?
