I always dump one quart in the converter, then I put the tranny in, then I add about for quarts to it, fire it up for a few seconds, shut it off, add more fluid (to specs if you know them). If you dont how much it takes to fill, then make sure to run it through all the gears (car doesn't have to be moving) then check your level and add if needed. The reason for priming the converter is to make sure the stator and turbine etc. is lubed before operating. Note you may even want to swish the fluid around inside the converter before installing.