Most likely your over length irons have a very high swing weight. So cutting them down to standard length or 1/4 inch over, will just bring them back to normal range. My wrist to floor measurement is 36.0, and I play standard length irons, so I don't see why you could do the same or maybe a bit longer, but not an inch longer for sure. What you might want to do, it choke down on all your irons 1/2 inch and see what you think. Then if you like the results, you can cut the shafts down and be done with it. Basicially the only thing you will notice if you cut down the shafts is the swing weight will be a lot lower, and the clubs will not feel as HEAD HEAVY as they are now. You might start hitting the ball more solidly with the shorter length, and that could end up giveing you more distance, not less. Solid contact means more to distance than any increase in club head speed you might lose with the shorter shafts.
Sorry but I can't tell you much about clubs for your son. You might want to ask a local club maker that works with kids. He should be able to tell you if your ladies set can be cut down to fit your son. I would ASSUME that you could do this, but I've never done it so I can't say for sure.
When you get ready to build a new set for yourself. I'd recommend you get a set of Leyland LX2 heads from CSG Golf. Thery are excellent iron head, and will last you for years. They are very close to the old Callaway X-16 irons. I've got a set I built when I first started building clubs, and I later built a second set for my wife, which she still uses.
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Putting is easy, IF you have the right putter.
Later, Don.