what is the exact size of the bolt behind the alt?

[arista5]

I am getting outfitted with a custom alt, but the hole in the rear needs to be tapped out, what size is it?

thanks

Length?
Diameter or width?
Threads?

Mine is about an hr away from me at this current moment.
thanks

 

[arista5]

ttt

 

[1FASTV6]

Originally posted by arista5
Sponsored by *www.gbodyparts.com*

 

[arista5]

artie whats the confusion? its not for racing.....