Joined: Sat Feb 04, 2006 8:59 am Posts: 549 Location: Stowe, VT
There is definitely less info on inside edges than T-nuts/inserts. Again I haven't done it, so I can't speak authoritatively. This place seems to be out of stock, but I just googled "DIY ski supplies" and this was the first obvious link it returned: http://www.skibuilders.com/store/materials.shtml .
Several people here have installed their own inside edges, so perhaps they can chime in. In particular, Monk151 makes beautiful aftermarket splits so perhaps look at his old posts to see if he has shared any pearls of wisdom on his techniques. I believe people have simply used a dremel tool very carefully.