I've removed the transmission and got most of the oil out. I've filled a 1 gallon milk jug about half full. That means there is still some left in the transmission case. What is the best way to get this out? I'm going to be participating in Dr Evil's transmission clinic and want to get all the oil out to keep the mess to a minimum.

I thought I might tip it up so it's bell side down and let the oil drain out where the throw out bearing is. Would I need to take off the parts around the spline shaft?

Or is there a better way?

You probably have most all of it out. it holds 2.5qts, so a little more than half a gallon I think. The way you explain would work (which means taking off the throw out bearing sleeve, then pulling the main seal).

You could probably roll the transmission over and let it drain through the air vent.

You can also remove the speedo drive and tip it down.

You don't want to wash it out with solvent. You want the gears covered with a bit of oil to prevent rusting.

Just in case you were thinking about doing this...

Once you pulled the side cover, that is the lowest point and it will come out. Only issue is if the oil is cold as it is like molasses then.