A 3" cutoff wheel works better, cut it at an angle or slice it down the middle to split it. A truck body shop should have the correct aluminum hucks and tool to pull them. I just did a friends here at work. It looks OEM when done.
I tried that, took longer and made a bit of mess. A sharp air chisel and they came off min or 2. Grinding took maybe 3-5 min per huck.
I used SS bolts, so next time i hit somthing i don;t have to cut them off again