I’ve considered this. It’s probably no easier that putting on a gas block.
It is infinitely easier. Unless you don’t have a cut-off grinder, or dremel, or sawsall, or hack saw, or file, or belt sander. Then it might be more difficult.
But then you can just slide it on and tighten the handguard screws. Easy. I cut off my first one as a neophyte that had no real tools.
If you go this route, be sure the handguard is compatible with a standard barrel nut, otherwise that will have to be changed too.
The only thing wrong with the Centurion is the exorbitant price really. It addresses your situation perfectly otherwise.
Just in case…
Have you looked at the Sampson handguards? They have an EX model that goes around the FSP for a longer grip and a nice rounded profile. But that requires removable and reinstallation of the FSP. And it isn’t MLok.
I am partial to Aero and have mostly enhanced ones. I have one ARStoner branded handguard from MidwayUSA that was inexpensive and is very lightweight, with Mlok slots. Makes my 22AR so svelt.
But this requires cutting the post or changing the block.
Then there are the proprietary barrel nuts or handguards like the LCR5 Carbon that require removing the barrel nut to install a receiver plate between the receiver and barrel nut. The handguard tightens on to it, sandwiching the barrel nut.
It isn’t as hard as it sounds once you get started. And besides, you have us!