oil level in strange top loader

just finishing off an alky funny car with a strange 9.5" top loader, when we bought the car the diff was full to the top with fluid, is this right? how much oil should we be running? also i noticed the diff has no breather should we be insatalling one?
thanks
aaron

 

the oil should be to the lowest point on the spool from the top. They have no vent. The air space takes up the pressure. It is lots of oil but they work well.

 

i also have a dragster with 9.5" fabricated housing should i be running this much oil in that as well?

 

511 we run a top loader in Ta/fc, seem like we run it about a inch to inch and a 1/2 below the lip of the plate cover. we do seem to always have a small leak from the front pinion seal. So at the start of this year we put a small vent in the top cover with a small tube that runs up to the puke tank. That leak is still there so I don't know if it did any good or not, but it seem to make the old man happy.