FIRST UPDATE:
Since I hate to give up on anything, I just spent about an hour yesterday porting the 2007 housing and managed to get the restricted ports opened up to larger than the 2011 housing's ports. There was lots of material there, no problem.
The next task is to open up the 2011's ports a bit now to match the early ones. I don't foresee any problems with flow now. By the way, I have solved all overheating problems with every big block swap I've done (Have done too many to remember) by using the water pump pulley from a mid 70's air conditioned Chrysler, it's about an inch smaller in diameter than the 60's stock pulley. It's shallower, so you have to move the alternator ahead 1 inch and use a two groove pulley on it and a four groove pulley on the crank, but this works so well I've never had overheating problems with any big block since I started doing this. I could go on with the long story of how I discovered this solution but you'd all fall asleep first.