Ford 3000 Coolant Plug Size/Type?

[Browntroutman]

Can anyone advise what type of plug is used on the Ford 3000 cooling jacket, just above the crankshaft at the rear of the engine? I am doing the clutch this weekend and just saw a dribble of antifreeze coming from the plug. It looks like a typical NPT pipe plug with a female fitting for a very large Allen/Hex key. I'd like to pull this out, and just need to know if its a dealer item, or just a common pipe plug. The last thing I need is to be stopped this weekend by the lack of a plug! Thanks guys!

 

[TractorTech]

The plug is a 1-1/2" - 11 x 1/2", PN 378862S Years: 01-JAN-65-30-JUN-68
If you can't find one, I have a new one on my Ebay.