With a 6" setback I'd expect you to be running with cav plate 2" above the hull on that Stratos.
Quite awhile back people started doing their own water pump service, and Marina's with "more important things to do" started throwing water pump service to thier flunkies. On some motors that's fine but on your V6 Evinrude there are a few little special things that need to be done when servicing the water pump.....or else you lose pump volume and pressure, and create excess wear on the lower pump plate. Basically if you don't know what "driveshaft preload" means ... then you have no business servicing the water pump on a 3 cyl, V4 or V6 Evinrude.
Anytime water pump pressure is in question the first step is to PROPERLY service the pump. You can't learn the proper way to do it on YouTube. I know because I've watched them all and snickered when they said "and that's all there is to it. . .Thanks for watching and please Subscribe".
There is also a service bulletin on 99-2000 Evinrude Ficht's that requires you to re-route the pisser hose. That hose needs to go over the Starboard cylinder head or else you are running with an air pocket in the cooling chamber. Water does not fully fill the block (above the bottom edge of the thermostat) if that hose is below the top of the uppermost cylinder head.
A good stream out the indicator (pee) hole shows that some pressure exists in the cooling system but it doesn't indicate anything at all about the volume of water moving through the system. To add to that....dash mounted water pressure guages are flakey, plain and simple, you can take 5 brand new ones and they'll all show different readings.