tuning
My.02
Hawk
As for when to do the tune, usually once you delve into the internals (cam) is when a tune is required, if you can see if you can get a deal where you get the car tuned (for full price), then for a retune the price is discounted
You'll benefit from a tune after the stall and rear gears (to set the trans shift points, and correct the speedo)
FWIW I'd do the lid, headers and rest of the exhaust, and the ported TB first, then do the stall, rear gears, and the cam, then get it tuned
Your beginning mod list looks good. But i wouldn't waste the money on the 3.73's since you're gonna put a stall in right away.

