@LeMans850i posted:… car jacked up in the air - ass high
You don't need to do that. Use a vacuum filling device instead. There won't be any air bubbles in the system. It's also a good device to use, to check for leaks. Before you put coolant in the system, pull a vacuum and leave it for a few hours or even overnight. If the vacuum drops, you have a leak.
I use an OEMTools 27066 Coolant System Refiller Kit. Less than $100 on Amazon and it works great.