Snapper WB 52 w/ Gobbler

First of all, pardon my ignorance, members. However, I cannot clearly see how to mount the hardware for the grass gobbler steel bagging unit onto the mower, specifically a Snapper Pro 52" WB. Nor can I see how the catch system works. I used to use another type for Lescos years ago, and it was cut and dry. This actually doesn't seem so. Can anyone help me out? Thanks.