you can use a simple patch cord and connect it to pri's in each switch.. all you need if your going to build a pri between two switchis two pair... on the rj-45 pins 1,2 4,5.. on a dn 9 pins 1,3 9-11.. they need to be rolled, ie on one end use 1,2 4,5 so the far end will have to be 4,5 1,2.. you do not need csu's for that ckt..
john poole
bellsouth business
columbia,sc