I think I added my coolant back into the radiator a little too quickly after I cleaned up and replaced the petcock, as I pulled out 3 gallons of coolant but only 2 will go back in. I’ve elevated the car and squeezed the hoses to help get some of the air out, and also opened the upper petcock while filling until fluid came out but still have lots more room for more coolant

I have a Lisle funnel. Would that be the best bet for burping in a situation where I think I need to add quite a bit more coolant or is there a better method?