As per the specs on XR irons, the stock shaft lengths are:
6i = 37.875"
PW = 35.75"
AW = 35.50"
SW = 35.25"
So, your 6I + 1" now is 38.875" long.
If you have already extended these two wedges 1" also, then you would extend their shaft length by 2".
If you have not already extended your wedges, you would be increasing the shaft length by 3".
A couple of things to consider:
Shaft length + loft helps determine how far a given golf club will launch the ball. If you make the wedge shafts 2 to 3 inches longer, you likely will get yardage compression. You might get a PW that flies longer than your 9i.
Safety factors: The clubsmiths at GolfWorks do not recommend extending non-putter shafts beyond 1". You run the risk of creating shear points, with club possibly coming apart.
If you like longer shafts in the short clubs, try the single-length irons.
I will be posting some next week sometime. I have been in the Fitness business for 20 years. These will include 3 levels for beginners, intermediate and Advanced so you can work your way up. I will also include some easy warm up drills. watch for my posts "Ten minutes to better golf " check out my ten minutes to pain free golf in the meantime