How eould you go about breaking in a trans? This video was probably after 8 miles on the trans hehe.Ahh, hell... no break-in required !
As long as it's working , go for it!
I am glad that you are getting to drive it!
I'm a fan of flogging
If it's gonna let loose, do it now and get it over with. If it can't take the abuse, it'll shit later anyway

I thought you were being nice to it, ran it up to only 5K and was pretty mild with no burnout.
Congrats on finally getting to drive this thing. I'm sure your happy.
I thought that you put the cooler in front of the radiator. Is that correct?
If so , you can do more driving than that. It's not that hot out , even were you are.
Airflow from the truck moving does a lot.