Transmission oil: How full is too full?

[Meanwhile]

Thanks! I’m pretty sure the oil level is safe, it sat parked for over 12 hours before I checked it. I put my little finger in a bit past 1st knuckle and it had a lot of oil on it. I kinda freaked out I guess when I found that leak thinking the worst and forgetting how far a teaspoon of oil can spread of time.

I had wondered about liquid VS air coolers and if an air cooler would be better. I have noticed that this truck shifts better in cool weather than when it’s hot out.

This isn’t a very good picture but I’ll post to show what I have.