c# SolidWorks API - Open file, Edit Classification Properties, Save File

I have tried to write this myself. I have a c# Windows Forms app that prompts for a folder of files. It then opens up each file using the Solidworks API. I am able to read the Custom Properties and the Classification Properties. I am able to add a new Custom Property and then save the file. I am close..... I need more: I need to be able to also delete some Classification Properties before saving the file. I have attached here my code so far.