Don't do it. They'll break.
I've got a fix for you. Take a Sharpie. Grab your irons. Start with your 3i. Write 4 on the bottom. Now take your 4i and write 5 on the bottom. Work your way up to 9 and write P on the bottom. Take your P and write an A on the bottom. Now you have a set of modern lofted irons that say Ping Eye 2 on them.
If you don't want to do that, just buy a newer set.