When gluing the lings in the rim it is always difficult to clean up the excess glue so, when it dries, it is not visible in the guitar. Rags, sticks, and other paraphernalia have been used to accomplish this feat. However, the best method I have found to insure the clean glue-up is about the simplest way to do it, i.e., simply flip the guitar body upside down. Then, any excess glue will, with the assist of gravity, recede behind the lings rather spill out. Here is a photo in my shop of doing exactly that. Turning it upside down also makes it much easier to do any minor cleanup!