Can you borrow a skill saw? I used a cheap cordless skill saw on my No Rez, and it worked perfectly (Sears brand).
I would discourage using a knife. When I tried brand new razors with my No Rez, it dulled them in one or two passes, which just leads to tearing and sloppy looks. Since your No Rez is visible (unlike mine) you want nice straight cuts. I would try to find a miter saw, table saw, skil saw or anything else that is sharp and spins really fast.
No Rez is tough as heck. I didn't believe until I tried cutting it myself.