air pockets have nothing to do with it... you'll basically be low like 3 qts on fluid.
My '97 FSM does not mention filling the torque converter before installing. That said, both the Nissan dealer and Level 10 recommended doing it.
Perhaps that means that it is not necessary. The torque converter holds 1/3 to 1/2 of the total fluid. If you installed it empty, try adding about half the fluid and idling the car while moving the selector through the various gears. At first it will not seem to engage, but the pump will be circulating the fluid. Check the level often, and add fluid as the converter is filled. It should be OK.
This is the procedure for my Mercury Mountaineer and Mercedes 500SEC. They have a drain plug in the torque converter to drain the fluid completely when changing the fluid.
yeah I think its ok to just through it on but everything I have read about people upgrading tq converters has always said to fill the tq converter before installing. that said, I think you'll be fine if you just refill the fluid after the pump fills up the converter.
so, fill it up until the dipstick level is good, then start the car, let it idle, then go to each gear for about 5 seconds each, go back to park, let car idle, and correct fluid level.