What did you end up putting on the threads? It needs either pipe dope or tape (or both); if not, it will leak. Unless it actually bottomed, yes, you can turn it another 180-degrees. If you used tape on the threads, you could try wrapping another layer or two on the threads, and that would cause it to tighten up at a different point. The threads are tapered, and if made properly (and that isn't a given!), you can normally get at least another 1/2 turn out of it. Because it is bent, normally, that lever is all you need to tighten things.