You asking about the rear end cap or front? Rear cap, use the spanners that came with the supressor. The front cap, I used the dead air ebrake wrench. My other suggestion would be to find some nails that are same size as the end cap holes, install 4 of them at 90 degree corners to form a square, get a couple of screw drivers, make and X shape of the screw drivers inside the nails protruding, engage opposing nails with the screw drivers and see if you can use that force to get the end cap off. A 30 minute soak in a carbon solvent may be needed prior to attempting this.
This is the ebrake wrench.
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