Has anyone with a C13 ever drained the coolant from the block (removed block drain)?

[CountryB]

I'm doing the coolant change ("green" ethylene glycol to CAT ELC) and I wanted to remove the engine block drain to thoroughly drain the coolant from the block, but I see no way to reach it (I can't even see it from bottom).

I removed the thermostat (CAT calls it a Regulator) so I know I'm getting flush water through the engine- but I would have really liked to remove the engine block drain - if it were possible.

So I'm wondering if anyone has ever been able to get their C13 drain (I think the way these engines are installed in Coaches, it is impossible).

The drain is supposed to be located on the bottom-rear of the oil cooler (here is a picture from the Adept Ape video - but I can't even "see" this location on my coach.

[1doodadd]

Mike, On my C12 I just continued to flush until the exiting coolant was gone and there was only clear water coming out, did not drain the block, couldn't reach it. I did run the engine the whole time during the flush, went for a drive first to bring to temp, took over an hour after I started to drain coolant. If your replacing the regulators, will you also replace the 2 regulator lip seals inside the housing?

[CountryB]

I will be replacing the regulator.
The C13 only has one regulator (unlike every other Cat engine which has two). I got the new lip seal and the housing sealing o-ring when I bought the regulator, ready to install.
Tonight I will install the new regulator and fill with distilled water, then run to hot and drain.
Then I'll add 8 gallons of concentrated ELC and finish by topping off with distilled water until full. That should give me a 50/50 mix. Cooling system holds 16 gallons total.