73 Charger prop valve fitting to rear line

[YY1]

Anyone know what size fitting this is? I know it's 3/16, and the same as a 5th Ave, but I don't know the threads. I only have one and I need another one. I suppose I could u-pull from another M body, but I'd like to know.Might be worth the shipping charge to save the time and labor.

My guess would be 9/16-18, as it's bigger than any of the other fittings I have.


Thanks.

 

[YY1]

It's 9/16-18!