trans oil replacement

[scott Baxter <rg500g@xxxxxxxxx>]

Have not replaced trans oil yet, but plan to this
weekend.  Don't have manual yet, and what I find on
Internet is not clear to me.  From what I've read,
I've got a drain bolt recessed deeply in a casting
below the fill point - allen head fill and external
hex drain.  Trans takes a quart, and full mark is oil
just starting to come back out the fill hole.  

Main question is:  how do you drain the oil and not
make a mess?  The side drain situation looks like a
catch trough is mandatory.  Filling is pretty
straightforward.  Put in 800 CCs to start, then top it
up slowly.  I have a funnel with a side fill
capability, but it has a goosenecked spout which won't
work for the topping up.  I'll need something with a
smooth neck for that.