I've used a couple of methods, both of which take time and are somewhat cumbersome. I'm sure there's a better way.
1. I have a pump (like a liquid soap pump from the bathroom) that fits on the gear lube bottles, and a clear tube that I feed from the pump into the tranny. It takes more pumps on that crazy thing to fill a tranny than it takes licks to get to the center of a tootsie roll pop. I think I got the pump in the outboard motor section of wal-mart - it's made for putting oil into outboards.
2. I have also used one of those huge syringes (again with a piece of clear tubing on the end) that are used to measure 2 cycle engine oil. And again, it takes a while.
As I was typing this, I remembered a little mechanical hand pump that I have packed away in the basement somewhere from my high school radio controlled airplane days. It was made for gasoline/alcohol fuel so I don't know how it would handle thicker oils. It is very precise and clean and could be used without hardly spilling a drop.
I also have a pump that fits on an electric hand drill, but the input and output are threaded for garden hoses. I suppose I could sacrifice a hose to cut the lengths I would need and give that a shot. It is much less precise that the mechanical hand pump I mentioned above. It would probably slosh and you would have much less control when you get close to full and would probably end up wearing a pint of oil.
Does anyone else have any bright ideas?
PS - I also work under the car on jackstands without much room.