@Thomas_Lerman Thanks so much for your reply. Being in Northwest Florida, there is definitely chance of freeze for a small part of the year … but I might take your suggestion and install it above ground and either get a rock formation or wrap it in the winter.
As to the manifolds, this is what I was considering: https://www.homedepot.com/p/Orbit-2-Valve-Inline-Manifold-Assembly-57250/202206756. I guess I was seeking out opinion if there was anything of better quality that I should consider since the reviews seem to be mixed on Amazon, Lowes, and Home Depot with this product. Thanks so much again!