How to install m9k weapons

A friend of mine recently have me his server login info because I offered to help install some addons to his ttt server while he’s busy. The only problem is, I have no idea how to install addons either. I’m trying to get clear instructions on how to install the M9K weapons pack, and haven’t found anything. Can someone give me instructions on hot to install the m9k pack onto a gmod server?

Information-

Server hosted through Xenon Servers
Server has no modifications currently

Do you want to use FastDL or WorkshopDL?

The server is hosted on Xenon Servers, which has FastDL set up by default. I’m assuming this will be the easiest way.

Then you’ll need to extract the M9K GMA using GMad and put the items on the server.