Checked the 2 engine strainers again and the lower one was still clean. I've done this 3 times since July 2018 to get a baseline of when they actually need cleaned. The upper one had two tiny stones lodged in the side ports. Looked like larger sand particles. Was able to push them in and they dropped out the larger holes in the bottom of the strainer/sprayer. I'll tackle the ones inside the lower clam shells in a bit.
I use my 4.6L V8 in brackish/saltwater allot and have always applied the Corrosion Guard to all the bolt heads, clamps, brass, screw in sensors, and any exposed aluminum. Keeps everything looking like new. I've never seen it discussed on here but even if you only dunk yours in freshwater it keeps any corrosion from forming. *Newspaper off the alternator belt area so it doesn't get on the belt or belt drive parts.
Corrosion guard
Strainers