According to TCI's website you don't need to use a radiator with the tranny lines going through it,UNLESS you live where it is below 0 degrees. See below:
The following is from their site:
Frequently Asked Questions
Should I use an external transmission cooler in conjunction with the oil cooler supplied in the radiator?
Answer: Unless operating in an environment where the outside temperature is below 0°F, you should cap off the radiator cooler line openings and run your cooler lines directly to a new cooler mounted in front of the radiator. This allows the transmission to have its own cooling system and doesn't allow the engine water temperature to heat the fluid.
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