HI!... The knock sensor on all the modular engines is located in the middle of the "LIFTER" valley, directly under the intake manifold. Due to FORD using a really long bolt to hold the knock sensor in place, you will have to remove the entire intake manifold to get it out. The bolt will back out and it's head will hit the bottom of the intake manifols plenum before totally coming out. Once you get it out install a stud and nut. This will make it 10 times easier to change next time. Do not use a shorter bolt due to the K/S uses the long bolt to help hear knock in the block.
This is what the K/S looks like :
Here it is installed in the block :