Answer
I would say for the average do it yourself kind of person the only "flush" you can do is take down the transmission oil pan, remove the transmission oil filter and replace it. be sure to replace the transmission oil pan gasket
if it has one. this is ok if you do it eextremely
60,000 miles, but if you take it to a place like jiffy lube they normally have a machine that can flush the complete system including the torque converter of the transmission. either way is acceptable.