Like the other guy said.  You will need to find your rails and stand to mount them on.  You will also need two ratchet winches to pull in.  Make sure you pin the arm on the ratchet mechanism under the clock and run the unloader while pulling it in.  You will also need to put a few metal pipes under the loader to support it and let it roll on. If the silage has been sitting for very long it will be like cement and difficult to pull, but it should go in. Also make sure it is short armed.  This is something though that I would not try myself as the service man will be able to service it properly and have all the right tools for installation. It will not be an easy job especially if you have never done it before and it needs to be serviced. 

good Luck