Where in the system do you plan on installing it? Did Eddie Marine give you any guidance on the location?

I would assume the correct place to install it would be before the sea pump. That hose is stronger and you'll always be supplying the pump with the correct pressure.
That's what makes sense to me anyway. I'm sure there is a opposing theory as well.

Not 100% sure, but I know it will be right before or right after the sea water pump, since that is the easiest area for me to get to, and route the line for the dump.

and no, Eddie marine has not given me anything. I ordered everything online, and didn't talk to anyone though. It doesn't look to be that big of job, and seems pretty staight forward.

Do the Mercruiser valves have replacement springs? Maybe they get weak over time and let the water out a bit earlier than it should......??

We plumbed right off the strainers, 25 lb pop off valve with a 3/4 discharge hose. This way the entire inlet is not subject to higher pressure with the speed increase

What do you guys think about mounting the discharge port? Shoot them out the back or run them out the sides of the boat?

I ask because my thought is you can see if your blowing pressure if you mount on the side of the boat. There is no way to tell if its coming out of the arse end.

You can get springs at http://www.mcmaster.com/

I welded bungs on the back side of the valve in my silent choice divertors. All the water gets dumped right the end of the exhaust. I have water press gauges in the dash that let me know what they are doing.

where did you splice in your gauge?

They aren't spliced. They are connected directly at the block.