Wait until you can start it up and let run a long time and get completely warmed up. If it subsides, it's piston slap. Stop this insanity until you're able to do that. Then if it doesn't quieten down some, you can go insane.
GOD BLESS YOU ROB!!!!!!! Brother, your Absolutely Correct.... and I Believe, if You had a printed version of " Rustys Guide to HotRodding Bliss" I rekin it'd be covered, probably many times..... Thank You. ..