How about this?

https://www.youtube.com/watch?v=CFZ9IM-OZOk

 

https://www.amazon.com/EPAuto-Radiator-Coolant-Filling-Funnel/dp/B01I40ZQWE/ref=asc_df_B01I40ZQWE/?tag=hyprod-20&linkCode=df0&hvadid=198151843411&hvpos=1o1&hvnetw=g&hvrand=9906904358167280641&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9060118&hvtargid=pla-381147636217&psc=1

 

https://www.homedepot.com/p/Lisle-Spill-Free-Funnel-LIS24680/206999882?cm_mmc=Shopping%7CG%7CVF%7CD59%7C23-16_GARAGE/GENERAL+ORGANIZE%7CNA%7CPLA%7CStorage_Garage_Smart_Test%7c71700000046870082%7c58700004743231957%7c92700040279481705&gclid=EAIaIQobChMIyMi2hfft3wIVg4bACh3-TgEsEAQYBCABEgIDYfD_BwE&gclsrc=aw.ds