8 string mandola with guitar body?

[Paudman]

I've always been a fan of the Irish folksinger Andy Irvine; the first tunes I ever played back around 1972 were his early folk tunes. I've played bouzouki and mandolin as well as guitar, but he has a beautiful guitar-bodied mandola built by Stefan Sobell, and the deep sound out of this is amazing.
I recently found a very nice 12 string guitar in a second-hand shop and got it for peanuts, with the idea forming in my head of changing the nut and bridge to make it an 8 string guitar-bodied mandola. Feasible?
The strings will be more widely spaced than the 12-string, and I'll use proper mandola strings but initially I'll need a blank nut I can cut for the eight strings, and probably a blank bridge insert as well... something I've never tried, but I'm handy with my hands and it's not EXACTLY rocket science... I hope. Pointers / advice / pitfalls please!

Here's Andy playing his mandola.
http://www.youtube.com/watch?v=bSk-FD_4 ... re=related
This one's not as good quality, but features more closeups of the mandola:
http://www.youtube.com/watch?v=hLP92-en ... re=related

[Paudman]

By judicious use of a Dremel drill and grinder I've cut and shaped a bone nut to replace the original 12-string version.
The problem is cutting it for the strings. I'm a mechanic so have plenty of feeler gauges to determine the gap, but cutting it may be a problem - none of my cutting discs are thin enough for the top strings, probably 0.10 inch.
What do the professionals use?

[JB]

We use hand files, everything you'll need can be found here ...

http://www.stewmac.com/shop/Tools/Special_tools_for_Nuts_and_saddles.html