Exact same thing here, 04 5.7 in my Cuda for about 14 years and no problems whatsoever. I did put a 6.1 cam in it and changed all the valve springs to the 6.1 exhaust springs before putting it in my car. I'm in the desert southwest ( it gets HOT here!) and I have hammered on it many times with no ill effects.
Mine has always had great oil pressure! 70 psi at start up, dropping down to 35-40 psi at idle when at operating temps.
