opinions on hooker headers

I was reading the installation instructions on the TTI headers and found this,

Remove the #7 tube from the header. Insert the header into
position from under the car. Before bolting to the cylinder head, slip the rear cylinder #7 tube in between the
frame and the torsion bar into the slip-connector (lightly grease the inside of slip) of the header

From what I'm reading does that mean the header comes apart?

If it does what keeps it from leaking?