For 18g wire, you'll need to trim the ends to about 5/8" / 18mm. This gives you enough length to create an average connecting loop. You may wish to double-check the amount of wire you use for loops, in case your loop sizes differ, and allow a little more end length.
To make this a true connecting link, make one loop 'horizontal', and the other loop 'vertical'. Before making the connecting loops: Position the links so each is 'facing upward', and the curves match. This assures that links will be symmetrical. You can then attach 'link to link'. You can also make identical loops on each end, and use jump rings to fasten the links together. This offers an additional way to add an Echo 8 link alternating with a bead link. Additionally, you can place a bead between the Echo 8 link and the connecting loop, at each end. Note the wire cutting lengths, above, for this option.