Grip shifters not opening on a Mongoose Terrex (trying to remove the shifting cable)
If you still need help, or someone else needs this, I just got one open. Take it off the bar. Take out the grub screw and separate the silver ring it goes in from the body. Looking down the hole from where the ring was, you’ll see locking fins (?) that hold the body together. You can use a screw driver to pop the fins off from the inside and it all comes apart.