Help with bolt size

Okay, I'm installing the turbo on my 99' eclipse GS. It is a hahn kit. I have to add a fitting to the oil pressure sending unit on the back of the engine... er towards the back of the car anyway. I have no Idea what size it is. I've conluded that it is between 1" and 1-1/16". Does anyone know what size that would be in metric? The largest metric tools I have only go to 24mm, so I have to go buy it. thanks!

Uhg this "kit" requires a LOT more work than just "easy do it yourself bolt on". I've had to modify almost half the parts. For anyone considering the Hahn kit, only attempt to do it yourself if you have a decent knowledge of cars. The kits instructions usually read like this "install new fuel pump", "attach new regulator"... That is as detailed as it gets sometimes. but... it'll be worth it.

Click here : ) (http://www.robdiesel.com/techinfo/Bikes/emergencySAE.htm)
I don't agree with some of his comments, but it will get you in the ballpark.