SLS Experts, Please

Hey folks,

So Yesterday I replaced the SLS accumulators on the S124, ride is MUCH better now.

I lost about 1L of fluid while changing the spheres (what was in them & their lines) however after the change when i started the car up to top up the reservoir, the level hadn't moved. This is with two guys sitting on the back, engine at 2k rpm etc... nothing. Took it for a drive around the block, still no movement. Ride height is normal, not sagging or too high.

I did the job at my parents place then drove it back to my house 15km away. Started it up this morning, still no decreased level in the reservoir.

So today I took the reservoir out and it was filled with a dark brown fluid with gunk at the bottom, cleaned that out and topped up with Penrite MB15 (MB343.0/ZHM equiv.) and ran the car with the return line disconnected.

It pumped out about 500ml's of the brown fluid and then ran clear (the colour of the Penrite) however it hasn't appeared to have pumped anything out from the rest of the system.

Is there a way I can completely flush the system of the old fluid? I've looked at quite a few articles on various forums and it's a bit confusing. Does the rear bleed valve do the whole system or just purge the accumulators?

Just wondering if there's a sure fire way to flush the whole thing out.

Cheers.