Been catching up on some basic maintenance lately...
Replaced Fuel Feed Line/ Temp Sensor (thanks to it killing the DDE)

Replaced Thermostat
Replaced Water Pump
Replaced Coolant Flange
Replaced Glow Plug controller and Glow Plugs
Replaced Vacuum Lines (went silicon for better or worse)
Replaced the (surprise, surprise) brittle CCV hose
Cleaned up Intake Manifold/Swirl Flaps/ EGR carbon deposits..
Replaced Gaskets (a couple were leaking oil all over the side of the block)
And replaced the Temp Sensor
And "Fuel Quality Control Valve" while I was in there
Also drained coolant in the process, but didn't get out as much as expected. Upon vacuum refill, it only took in just shy of a gallon? My understanding is capacity is just shy of 2 gallons?
I removed the lowermost hose I could find to drain, but seems there was still a lot left in the system after doing so. So I may end up draining and filling again to try to get as much fresh coolant (BMW Blue 50/50 with distilled water) in there as possible?
On the opposite end of the spectrum..
'Vacuumed' the fluid out of the power steering reservoir with a large syringe..
And directly opposite the coolant situation, got a full liter out..
Which seem to be the stated system capacity?
Again, may to the same process in a few hundred miles to try to exchange as much fluid as possible?