Is the removal of the "trunk springs" necessary for CF trunk installation?
If so, where exactly is the "spring" ?

 

The real reason to remove the trunk springs from an OEM trunk when installing a CF trunk is simply because the OEM trunk is heavier than the CF trunk (most likely, anyway). With springs installed that are too stuff, the trunk will turn in to a mellon launcher - when the trunk is released, it will fling up much more violently than usual. The trunk springs are located in the top right corner of the picture below, the black rod going left to right in the trunk. It's a torsion spring so it relies on flexing the bar for spring.

 

i had to remove both of mine because it tweaked the trunk upward when it was closed

 

That too.

 

Take them off.

My truck got hair line cracks by the mounts because of the springs.

I took the key latch off and used the metal rod from that as a prop rod. Kinda ghetto but it worked.