Help with Timing

hi all,i need help timing the 360 in my 72 Duster.Since its not stock and pretty sure it has a cam,I cant set it right without it dying,and was told I need a timing light with an advance.Well,i have a advance timing light on the way and want to know how to use this light to adjust my timing.Someone told me in my last thread which I cant find to set it 30 degrees @ 2500 RPM.I have it set to where it starts ok,will not stall,but I feel the motor should be alot more powerful than it is right now.Any help would be appreciated.thanks

PS:Someone also suggested timing tape