[a6m5zerosen]

I have three cars that I need to flush the automatic transmissions and change their filters. The filter change is easy enough, but what's the best way to fully flush the transmision, pump, cooler lines, and cooler? Shops around here want between 80 and 100 bucks to do it, and that's just the flush-no filter change. It can't be that tough, but I wouldn't want to damage anything. The transmissions are a '71 turbo 400, a '77 turbo 350, and an '85 200-4R. Thanks for any input.