[Ed_Strong]

That is great stuzman, I was thinking I was all the only one trying to do this, very little info out there on this trannys in regards to images and illustrations.
xeroinfinity was giving me very good advice and directions on what works best and how to avoid trouble.
Like you I want to get rid of all the old Dexron III and replace it with Dexron VI. I also got the fluid from Walmart, you really can't beat their price!
If I'm following your instructions correctly, the only issue I see with your procedure is that by disconnecting the bottom line at the cooler (radiator side) will bring the old fluid from the tranny into the waste bucket, but will not allow the cooler to get flushed, leaving the old fluid still in it! How did you get around this?

According to the directions from xeroinfinity I am to remove the trans out, raditor in(top hose), from the radiator, and let that run into a bucket. I think your Impala has the 4t65 and maybe my 4t45e is different!

Another question... what's a 3/8" jiffy-tite removal tool? And how does it make it easier to remove the oil cooler line?

Looking at the cooler connections at the radiator all I see is a "half dollar" size flat washer encrusted into the plastic and then the line's nut securing the cooler line in place. That's new to me from the old style that needed 2 wrenches to undo the lines. So, I'm afraid to ruin the radiator by applying too much or the wrong force.