Remove the two bolts, then "wiggle" the two sections and they will separate. Do the same for the other end to make it the size you need it. If you are lucky, the push nipples will stay where you need them and come out where you don't. Otherwise you will have to use a wrench to "twist them" so the come out. If you can get four of them without wrench marks you can apply pipe joint compound to them and put them back into the openings. Push the sections together and reinstall the bolts. We used a tool to press them together and then installed the bolts but you don't have that.