Hex plug dimension?

[larryM]

I am trying to find the dimension for an internal hex plug that goes into the Christen oil valve. I want to remove the existing plug and wondering what size of hex wrench is required. I wouldn't normally bother you with it, but I will have to buy the wrench and if you know off hand it will save me a half day and about 30 miles or more of driving to check it out.

Sometimes internet can be my worst enemy! stated after a frustrating half hour of googleing it!

Thanks!!
larry

 

[smizo]

 

[larryM]

 

[bumper]