Tom, you should be able to reach the block drain fittings by sitting in the bilge and reaching around the engine mounts to see/get to a fitting (keel side). You really want a block or thermostat housing reading.

I'll look/feel for it.
I assumed that block/thermostat reading was not close enough to the source (raw pump) and that a closed thermostat might interfere with my readings...I (thought I) wanted water pump out (no interference) data...what is my mistake/error, once again, I'm learning.

Has anyone experienced the needle over pegging over the winter lay up. It’s happened twice on me. I suspect it’s due to water trapped in the gauge. No I gotta get in the habit to drain it before fall lay up

I haven't but what size tubing is feeding the gauge, I'm using 1/8 which has about 1/16 ID?

Ours is also on the block...where a freeze plug would normally be.