It's ok to leave the diff cover off for two days right? With a towel over it. I drained fluid and pulled cover off then had a family emergency. Will not be able to get to sealing it and filling it till tomarrow afternoon.

 

yeah, should be fine.

 

As long as all the metal parts are soaked in oil & the the car is indoors or at least in a place where a breeze isn't gonna blow dust into the housing, you should be fine