Power Steering Fluid/Flush Question

[Cali' Explorer]

Hey all, did some searching on this but haven't found a definitive answer yet.

I want to do a Power Steering Fluid Flush on my X. It has about 85K miles on it, and I was recently told by the local shop that I have do my oil changes that the fluid looked like it needed to be replaced (very dark, checked it out myself). I was just going to do a flush myself using the methods listed in my Haynes manual.

The problem I'm running into is deciding what Power Steering fluid I should run. My Haynes manual says to use regular Mercon ATF in the Power Steering pump. I was hoping to go to a full Synthetic fluid to hopefully increase the life and performance of the Power Steering Pump. What I'm trying to decide is should I just stick with the basic Mercon ATF, with regular "Power Steering Fluid", "Synthetic Power Steering Fluid" or Mercon V ATF (Synth)? I personally would prefer to run synthetic just because my experience with Synthetic has always been good, but I don't want to damage my X either (This X has to last me through another 3 years of school without any major repairs).

Also, anyone with a '97 5.0, or one with the White "See Through" Power Steering Fluid Reservoir, do you have a hard time seeing through the window to see the level? I have tried cleaning the outside and haven't come up with a solution to make it clear enough that I can see what the Power Steering fluid level is inside. I've been using a jury rigged metal bar with a high tech "stop" so I can accurately measure inside and then pull it out and measure against the line on the outside of the can, but I want to get it cleaned and use it like its meant to be.

Sorry for the long thread, thanks for any help you can give =).