Without drilling? Hmmm, I can't say that I've heard of that.
If your Cooey came without the 3/8th's dovetail on top of the receiver, then I think drilling is your only option.
I bought my 600 already drilled and tapped for what I was told is a Weaver #4 side mount. I still haven't bothered to scope it though, as the irons work perfectly for me and the mounts, rings, and scope combined would be worth as much as the rifle, if not more so.