Ok, I think I’ve got this figured out. The bagger in the MyTractor forum is not the OEM side bagging used on a 10525 model, but one adapted from an different model. The side bagging system for a 10525 should be kit number 89817, which uses bag number 89816. From your postings I’m assuming (yes I know I should do that) that you have a rear mounted bagging setup on your unit. The replacement bag part number is 100-6362.