When I changed mine rear diff lube, I ran the car for about 14 miles into town and back. That got the rear diff warmed up nice, the oil wasn't hot enough to burn when it spilt over my hand.
You want to pull the fill plug first (that's the plug near the top of the diff) because it may be stuck. If stuck and you pulled the drain plug first, how would you ever refill??
Use your ramps. Just back up on the VERY slow and careful, none of these high speed ramp runs into the home gym, OK.
You should have enough room for a one gallon milk jug and funnel. You can drain it directly into the jug, and since you are here in California, you should be able to put the jug out with the recycling bin on trash day. Our waste management company allows two gallons of used oil per recycling day (every other week).
Don't try to filter the gear oil through cheese cloth as you are draining. The oil is too thick and even warmed it will overflow the funnel.
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.