Ok so it's leaking at the collector? Do the headers you have have three bolt flanges, or is it a slip connection?
If you have 3 bolt flanges try some Percy's Seal-4-Good gaskets, they work great!
Also I was wondering do the 4v hookers have a two piece design on the drivers side, with a slip connection on two of the primaries before the collector? That's how my flowtechs are, and that gets super super leaky real fast, I ended up JB-welding mine this last time!
its the slip connection and yeah it has the 2 piece.. but thats not whats leaking. it is the collector itself.
edit* no I am sorry I misunderstood. the hookers dont have that type of 2 piece. they have a 2 piece x pipe on the drivers side with 2 slip connections.