Need some head, help

I agree there might be something there - but honestly - for a cruiser that' salready cruising - the purchase, gaskets, and misc stuff to swap them - the gain wouldn't be that noticable. It's not like it's got a cam that's getting anywhere near peak flow anyway so given the improvements in terms of valve job and whatever they did (guessing again it's not max prted but more of a "cleaned up" deal) the two would be comparable in the lift ranges of the camshaft. There might be a little more flow, but you have the larger chambers. So you incur more cost to mill...
As I said - it just ain't worth it.