What you describe is exactly what I will be putting these heads on (.030 over 340). As for Bolt and Go, I have not yet seen any reason why you could not but I am still skeptical and will double check everything first. Especially the valve springs as I will be running a fair stout cam (Lunati - [FONT=Arial, Helvetica, sans-serif]Duration 276/284, Lift .513/.533). Also like others have said, Gotta check the piston height and use the right thickness head gasket.
As for how these compare to stock X Heads?? I strongly believe they will flow MUCH better and deliver a lot more horse power. I do plan on buying some Dyno time once everything is all together. I do happen to have a fresh set of X Heads, A set of J heads with 2.02`s and a set of older econo W2`s all sitting on the shelf. I wish I had the time and money to do a side by side on all 4 set[/FONT][FONT=Arial, Helvetica, sans-serif]s but that is pretty unlikely.
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