I usually take off the front p/s wheel and run a flexible tube though the wheel well to it. I vacc'd the old stuff out the first two times I changed the fluid, now i simply run two bottles of the fluid through effectively flushing out the very dark grey crap until it runs clear, similar to the older rear diffs and allow it to leak out the hole until it stops running and stick my pinky in the hole so the fluid is up to the bottom of the hole then replace the plug.
