How to flush a toploader

How do you go about flushing a toploader? I have it out of the car now, so its probably easier to do before I put it back in. Theres a nice sludge in the bottom of the case.

When I flush my toploader I usually put the lid down and hit the chrome handle on the right. That'll get rid of the nasty sludge and everything in one fell swoop!
But seriously . . .

I put mine in a parts washer with the tranny top off & drain plug out.
[addsig]

so I guess that its okay to spary the syncros and shafts with solvent then? I thought that it might screw them up.

Won't hurt anything internal, might want to change the seals/o-rings, unless you use a mild cleaner like diesel
[addsig]

Ok cool. I was going to replace the seals anyway. Thanks.