Just installled my headers this weekend just to help everyone out the bottom of the headers dont have threads for the bolt to go into well it least mines didnt before you do u get some nuts for 14mm (i think). Also you do not have to use the bottom paper gasket that comes with the kit the donut gasket does juts fine. Hope this help

 

Yeah, I was going to post this same thing. I just got done with mine. I was real dissapointed to see that this header didnt have threads tapped into it. So off to the hardware store I went to get some nuts.
Also, I ended up having to get a big washer to put between the spring and the head of the bolt to put more pressure on the spring to get a good fit (I still think I have a small leak, but maybe it will set itself over time).

It took me 3 hrs. and I look like I just got into as fight with a large cat but its done!!!!!!!!!

 

Also, make sure you have the gasket on the block facing the right way, or you wont get the 3 middle bolts on!

 

The newer headers have the threaded holes the first gens were clean holes.

 

chicks dig scars ;)

 

was there a noise on start up after you installed the header?