Hello nickld and Welcome.
Just because it will accept PC accessories doesn't mean the plate holes will match.
I don't know about the compatibility of the Ridgid plate holes but I do have a suggestion if no one else knows. Take the base plate off the Ridgid and take it with you to get your new base so you can compare it to some of the pre-drilled plates, or just try to match it with the bases of the other routers. If you find a match you will know what to get.
