Basic rules for tuning up points ign. cars.
Always set dwell 1st. 30 deg. for any v8 gm.
Always set timing 2nd. Make sure vac advance is unpluged.
Adjust carb last.
Reason for this: dwell makes a difference in timing, and carb tune up. timing only messes with carb tune up. Adjusting carb will not make any difference in dwell or timing.
You use the vac gauge just like you would the tac. look for the best vac reading when adjusting the carb.
Do it right and you get.....
