i have a borg warner 9 bolt rear i want to swap in my 92 rs. i draind all the old fluid out and want to fill it back up but not to sure how much to put in there. i know that plastic car it to fill hole but i am not sure how to get it out without messing it up i really dont want it to leak after prying it out. so my question would be how much should i put in there befor i seal it up. also do you think the royal purple syn oil should be good.thanks for any help.

 

Fill to the plug level. As soon as it starts to overflow, it's full.

Obviously have to have the whole axle installed to get the correct angle, to avoid over or underfilling.