Correct Spark Plug Gap
 

I have a 1971 Impala Convertible with 350 motor, new Edelbrock Performer 600 cfm carb w/electric choke andEdelbrock Intake. I just converted to the Accel HEI distributor.My question is, what are the best spark plugs to use and correct gap? I have been using AC Delco plugs. The spec calls for 0.035 but since Ive upgraded Im thinking it should be more like 0.040-0.045 for my gap? Need a little input. Should be an easy one! :)

Thanks.