900$ Trany rebuild?

This will be a 375ish hp cruiser with 3.55s...No need for super high converter.
The damage most likely occurred while this trany was behind my W2 Solid roller 360 in another car.
The thing is that since I installed it in the Barracuda along with the new 2500 stall TC.. I have dropped the pan twice and each time it was super clean....
I suspect that what he is telling me about the trany is true but I am hesitant to replace a converter with a few hundred miles on it.