Fuel door spring screw

I recently bought a new fuel door because the original rusted at the hinge and broke off. I bought a replacement but the vendor who sold the door did not include the spring that latches to a little post on the body. I had to buy that part but I don't know what size screw it takes to mount it to the door. Anyone know what size screw it takes.

 

You might find better info if you post in the 2nd Gen section.

 

There is a screw hole on the far left about midway on the door itself

 

Are you referring to the 2011 Tacoma from your profile, if so the 2nd gen forum is where you want to be.