Carp,
You should not have any problem with that small amount of Classic AFT. Like others have said, that small amount will not cause any damage. Transmission fluid provides two basic needs. 1) it provides the correct friction pressure to drive the selected clutches and 2) it provides cooling for the transmission parts. High temperatures from too much friction and not enough cooling is what kills transmissions.
In my case, I run a modified C4 with Kevlar clutches. For proper friction pressure and cooling I have to use Mercon V fluid. I also have a trans temp gauge on the cowl to make sure I don't get into trouble.
I also recommend when ever you check the transmission fluid level of any transmission, use a white rag or paper towel. Besides making sure the level is correct, wipe the dip stick off with the rag or towel. Check the color for a red or dark pink. If you see a brown color, that indicates burnt fluid. Smelling the fluid will also give you clues. A burnt smell also means trouble.
When I look for used cars, street, drag, whatever. I make sure the selling party does not run the engine. The first things I check is the color and smell of the oil and trans fluids.
Rest easy and don't worry about it.
Dick