A case of Crs.Again.. Cutting Styro for Wiring

I cant remember nuttin this evenin or should I say mornin now.... Bad case of CRS ....
Has it been mentioned at all as to how to go about making a nice groove cut in styro insulation for the electrical wiring? Ok other than a knife..
Mine will be inside of flexible coil... (plastic) but Id like to make the cut out so it looks nicely done even though it wont be seen...
Here is what I mean.. the wiring is already inside of this premade..
But Im Finnicky by Nature...
Cant help myself...
Classic Finn

Has it been mentioned at all as to how to go about making a nice groove cut in styro insulation for the electrical wiring? Ok other than a knife..
Mine will be inside of flexible coil... (plastic) but Id like to make the cut out so it looks nicely done even though it wont be seen...
Here is what I mean.. the wiring is already inside of this premade..
But Im Finnicky by Nature...





Classic Finn
