Recommendations for an aftermarket aux Transmission Cooler w/ thermostat/bypass?

I was wondering if anyone has a good suggestion for a relatively easy to install aftermarket  TOC with a thermostat controlled bypass, & a fan for cooling while stopped/in traffic?  It'd be on a GMT 900 platform 2011 5.3L 3.08 gear ratio. 

Try B&M

I went with a B&M and even without the fan it does an amazing job.  Go for the stacked plate design.