Originally Posted by daisuke149

personally, I dont think silicone is all that necessary, best is as you mentioned, loosen it all up, then starting from the test pipes, tighten each piece one by one, holding them in position (generally up a bit, higher than where it should be as it would sag down a bit)

keep the hangers tigheted and in place though, those will help align the stuff as you tighten them.