This is what I did on my 3-9:
No cutting and lost .35"
For those that asked, I removed the turret, o ring, and collar (it's just glued on) so that I was left with the straight cylindrical turret housing. I then cut one of these to fit:
Steel wool took the shine off.
It fits very tightly but if I can figure out the thread they use for the turret screw I may mechanically attach it as well.