PTP

So in a '98 Max w/ 66K on it I wanna switch it over to synthetic tranny fluid(its a automatic). I was thinking about just draining the old ATF out and just refilling w/ new synthetic ATF for the first time(versus the whole drop the pan and clean it out) because I heard when you first change to synthetic it cleans out the gears much more than the old non-synthetic ATF and a second drain/fill is called for.
So I after the first drain and fill I was thinking about then dropping the pan and cleaning the whole thing like 5k to 10K miles later. Does this sound reasonable/intelligent?