adding a transmission cooler

I see a lot of people have trouble when something breaks in their rad and their tranny fluid and coolant get cross contaminated. I know that if the coolant mixes into your tranny fluid, you can end up pretty screwed.....

Is it a good idea to install an aftermarket tranny cooler that is separate from the rad? If they're not connected anywhere, they can't get cross contaminated, right?

Would you also have to replace your rad, or could you just seal off the old lines from the tranny?

Thoughts? Estimates of price? Where the heck would it get installed in a 2002 3.3L grand caravan, since the fans on the rad take up all the space.

Try this company
http://www.derale.com/main.shtml
You would probably mount the cooler in front of your Radiator using a nylon bolt "thru the Radiator" mounting kit.