long shot but...

To the original question, No it won't seal up.

Sorry if I misunderstood, but it is in the car or not yet?

A few more details explained could save you some headaches.

The spring on the inside of the seal can pop off when you tap the seal in, and if unnoticed can get wound up in the pump. (BAD)
Filling the back of the seal with assy lube will keep that from happening (just so you know in the future)
And yes, it can leak from this without ever being started because the converter fluid can get by the seal as it tries to run back into the trans.

Point is, right now it's a very minor deal.
Start it, and it could be a real disaster.