Very nice work as always Jeff..........
I don't want to hijack your thread, just borrow it to say I took the opportunity to install a new thermostat in my OHC yesterday. I grabbed a bucket, wiped it clean, drained the antifreeze into the bucket and went to the parts store to get a new thermostat and gasket. I swapped it out and go to add the antifreeze back in to the radiator and my bucket is empty.
At my age of 66 I had a moment of pause to ask myself, did I already pour it back in?
And then I see this tiny crack in the bottom of the bucket and then I look under the car and the cardboard I had placed under the engine for drips, is now soaked in antifreeze.
Ahhhhhhhhh I laughed at myself

and the whole incident. I thought when it ain't broke don't fix it came to mind. So be careful.......Murphy's law is lurking when you least expect it.
Well off to get new antifreeze. I guess it was time to change it out ...anyway, as I console myself.
Now back to Jeff's regularly scheduled program.................