No, I do not cut to size. I like to make sure the new tangs do not align where the old ones were. I use a fiberglass cut wheel and if binding I will trim and overhang the binding. Then round over the ends. Helical I believe they call it.
Bolt on is where it is fast. Remove and if you have no tear out, which I do not. I mark the fingerboard with light white grease pencil in a zig zag. In this case I was installing a 9.5 radius neck on a Thin line. I use 320 wet sand on 12 in lon 9.5 radius standing block. When the white is gone, board is flat. Luckily, this one was. Sometimes you have To refinish. I do on mine and this one is mine. The new neck and a Nice amber color. So ready for install.
I use a press and one drop of CA glue at the center of the fret. I always coil the frets with a little more radius. The old radius blocks are cut and used to press the fret. By the time you areready for fret 2, one is séated. And so on until will are there in place. To avoid pop ups the glue works well.
To cut to size on the ends, I put a Thin strip of metal like a feeler gauge. I cut them from .005 metal sheets. These get put under the overhanging frets. Again, the cutting wheel. The metal strip protects as you cut from the bottom up and now you have a very slight overhang. Big file, now this thing is covered in Kraft tape, which I prefer as it is much tougher than blue tape. Take them to the tape with a file.
I have a round over block cut with a 30 degree I sand the edge. Mark the frets with a sharpie. Sand flat 320, till almost all gone and switch to 800 so when gone I have an easier polish coming.
The file for crowning will get the ends fine. Mark and crown. Buffing wheel, remove tape and install.
The 2 tools work very well, and actually will more than cut my time in half.