Does anyone have experience removing material to get an 11s road cassette onto a 10s hub?
As per the hub standards, the difference between the width of a 10s and 11s freehub body is 1.85mm. The back of the cassette I'm considering (11-28t shimano CS-R7000) has plenty of material that could be removed from the aluminium block that holds the 4 biggest cogs, including a small (~0.5mm?) lip that could be taken off evenly with relative ease. I'm worried about removing material symmetrically past that, as any divergence from planar would cause the cassette to sit unevenly on the freehub stops and wobble.
There's also a bit of material I could remove from the stops on the freehub body, though I'd be happier to ruin this cassette than have to replace the hub if this goes wrong. I've been (past ~2 years) using an 11s HG800 cassette which fits 10s hubs and dishes slightly, so I'm not worried about spoke clearance as the distance from the dropout to the big cog should be the same (or less if it's a tight fit). It's a Fulcrum 7 wheelset but the hubs are unmarked, rear one is 24h, 8L/16R.
I don't have access to a machine shop, but I've got a die grinder/dremel/angle grinder/files etc.
Has anyone tried this? Did you have trouble removing material in a radially symmetric way? I do see this poorly-received answer to a related question, though he says it must be done by a qualified machine shop (like his company).
Edit 1: I do see that I can get a compatible replacement freehub body for ~$100, which is not cheap but is a reasonable alternative/backup option
Edit 2: Thank you everyone for the informed advice. I'm going to try taking material off of the freehub body but plan on replacing it with a real 11s body if it doesn't work out.