Does trans fluid wear out

I am planing to do some drag, and a bit of street driving, I hate traffic, it is an A/C car, but I removed it, (fixing to get my tag n ins, YES!) and it's about to really hot in FL.. Took me 5 years to get this far. And I am just a carpenter, so I would rather spend a little more now than a lot more later. My other Mopars were 4 spds, so i have never had a good build w/ an auto. And I would not have w/out help from you great guys on this forum. What size cooler/ fan would you recommend? Thank You!
PS
1970duster
Can I borrow your cup-holder?
http://www.summitracing.com/search/Part-Type/Fluid-Coolers-with-Fan/?keyword=transmission+coolers

For your setup, I'd use one with a fan that does AT LEAST 500 cfm (600 cfm min would be better for the super hot days) but that monster 1500 cfm would be over kill. This link will let you choose the one that best fit your budget.

PS
That cup holder is great aint it!