rocker arms tapping

IT is easy, start the engine and get it warmed up. shut it off and remove the rocker cover. Start it up again, slow your idle speed if you can. All you need to adjust them is a 3/8 box wrench and feeler gages 0.02" for exhaust and 0.01" for intake. with the engine running slide the feeler gage inbetween the rocker and the valve stem, there should be some resistance but it should go in. If it slides right in (which is usually what causes the engine to tap) you want to turn the adjuster clockwise. if the feeler gage won't go in turn the adjuster counter clock wise untill the feeler goes in snugly.
I just adjusted the rockers on the 66 Dart Vert I bought last weekend, it was so loud the seller thought tha engine needed a rebuild. Every valve was loose, I snugged them all up and now it purrs.
People will tell you to do it hot not running but believe me running is best, and there really is little mess if your idle is low, if you rev it up you will fling oil everywhere. Make sure at this time you are geting oil to all the valves, you can tell if the feeler gages get oily as you adjust them.
Goold luck