Don't et me wrong, I've done it.... but you really shouldn't. The breechface was already widened to accomodate 9MM and you risk the TCM brass having too much breechface if you widen it.
The 9MM slides will however accomodate it as mentioned above relating to the video I have on it... if you can pick up a 9MM slide then you could use it with a 38 super barrel and be good to go... maybe I'll do it to one of mine to prove to you it works on camera but I have converted many 9mm's to 38 Supers.
So, yeah... It "Will" work... but really you shouldn't.... a 38 super's case head is basically the exact same size as the breechface and has no breathing room for case and brass variations (which is why it will fit on the 9mm's face, the tolerances are opened up to accomodate for 9mm's variations, which happens to be big enough and close enough to the 38 supers!"
I hope this helps!
SORRY for the late reply, I had a hellacious work week this week!!!!!