My custom trans cooler mounts

Nice clean mounts!
The only thing I may have done differently would have been to turn them over and mount them on the top side of your mounts so the mounts would act as a bit of a protector for them. The hose connections could be made directly through the holes in the mounts.
It probably would necessitate mounting the coolers to the mounts first and then attach the entire assembly to the floor. That way you would be able to tighten the hose connections to the coolers.
You would also have to remove the cooler/mount assembly in order to service the coolers if needed.
I think the airflow would still be more than sufficient.