A friendly suggestion while you have it apart is to consider replacing the crankshaft with a forged 6.1 crank or aftermarket crank. The forged 6.4 crankshaft would also probably work, but I would double check. It would be a different stroke while the 6.1 is the same. The stock rods and pistons are the weakest part of the rotating assembly. If you can, I would replace the stock powered metal rods and fragile pistons with forged high quality components. Just my 2 cents.
He'll be fine with the stock 14 parts they are much better then the pre Eagle stuff, I've seen guys put 250shot of NOS to the newer short blocks plus there are afew guys(one post here ) that are boosting the newer eagles to 12lbs no issues unlike the pre Eagles which seem to explode @ 10lbs.When they redesigned the 5.7 they moved the top piston ring down and opened up the top gap , don't know the exact amounts .
