I’ve done a few, a hacksaw and a few decent files are all you need, bigger problem is touch up. Easier to cerakote the rail after. If you don’t care about looks paint or a black touch up pin are also doable.
Biggest concern is making sure you will be able to reseat the the taper pins. Often you can get a punch through the handguard vent holes. But you may need to open them up
They make rails for that. It might be just as cost affective to purchase a pre fit rail. They would be easier to remove if need be since it's built into the design.