Tip trim irons AP1

In the past I have tip trimmed driver shafts to lower ball flight or change the stiffness.  Could I have my irons tip trimmed?  If so, can I send my irons to Titleist to have this done and how much would it cost?  Tip trimming a driver is common but I don't recall if tip trimming irons is common.  My irons are AP1 712 with graphite shafts. 

Hi,  We use taper tipped shafts in our irons (vs parallel tips in the woods) and will not tip trim those.  You can hard step them as long as we have 36.5" shafts for the wedges. 

I have the new AP1 714 irons. I'm thinking about putting in graphite shafts instead of the steel. Can I use UST Proforce Rv2 75 Gold? TIP size 370 , Parallell.

They need to be .355 taper tipped shafts to fit into the heads.