+1 to get the HD kit. It is a lot of hard physical work to tear it all down and replace. Not technically difficult but physical. Did mine over two weekends. I jacked up the entire trailer frame onto jack stands, removed the wheels for better access, and used the jack to support one axle at a time during the swap. I was replacing my flatted springs at the same time so no shortcuts. Possibly one shackle could be done with a single lift point but really best to do the whole thing. OK to just drag it to a shop if needed.