I have done it a couple times now. I figured there were 2 ways of doing it. One is to insert the guide first, then put in the end of the screw or the "keeper" tube in the picture, and load balls in the first ball loop. Then move on to the next loop and fill that one up and repeat the process until your finnished. I found this to be too hard, so I just chopped off the legs on the guide and stuffed the balls down there with the screw in place. When all the balls were in, I put the guide into the hole again. The only thing keeping the guide in place is the mounting block. Not perfect, but it does work. Good luck!