I picked up a 17466 from Advance Auto. The tech/archive post above states that it is 21 mm shorter than the others. At the bottom of the motor there is only 3/8" clearance from the 2 1/8 hemi headers from TTI. That is the tightest point on the install. So I go to mount on the header and pull the gaskets out of the box and find out they are for a 340. They shipped me the wrong ones with the hemi headers. I'll never finish the car at this rate.