Thanks, I put a bit more thought into it and here's what I did:
I ended up taking out (breaking off) the back of the cap since I will be putting in my own scope decal w/clear plastic there anyway. Once that was done (got rid of the sharp edges with my rotary tool), I then saw the little "lip" where the cap goes and was then able to shove a thin screwdriver to help break the seal. Once that was done, the cap slid off. I will be recreating a new ring edge using MagicSculp but now also see that inside, at the top of the back of the scope there's a post that I need to cut off & file down as that will block a little bit of the LED light I plan on installing.
I thought about using one of my X-Acto blades, but wanted something thin enough to pry in there, as well as use it to gently lift it to make the adjacent areas open up, so I ended up using a jewelry flat head tool as it can handle that kind of pressure better than an X-Acto blade.