Can anyone tell me what the size is for the drain plug on a '76 280z?  The service manual doesn't give it.  I found this size at hybridz (M16.4 - 1.33) but I'm not sure I trust it. 

Post the Hybridz link and somebody could probably tell you if it's trustworthy.  That is an odd spec. though.

Here's the link but I was really hoping someone could just tell me the size.

 

http://forums.hybridz.org/topic/111395-280-fuel-tank-drain-plug/

Never mind!  I found it.  

Funny it was in a box I have looked in twice.  Third time was the charm.