You could probably siphon or pump some out through the fill pipe... maybe get a 12v fuel pump and stick the inlet hose inside the tube. Maybe you could drill through the drain bolt and get most of it that way.

An alternate suggestion would be to put a large pan under the transmission pan, loosen the bolts a little at a time and let it drain out of the sides until you get to the pan gasket level - then remove the bolts on one end until the remaining oil dumps out of the end of the pan.

Yes, the linkage has to be removed - it's not as bad as it looks.... you'll be able to figure out how it goes back together.

Frank