I have NRG HD-300 hood damper in my FX35 and that's the one everyone uses on their FX on here. The HD-300 was made for the 350Z. I found its a bit too short leaving the hood fully opened too low. If you work under hood enough, you will bang your forehead going in or back of your head coming out :smile (2): . I went through lots of trouble to have them sent me the extension pieces in the red circle in the picture below.
Here is a picture of what will be included in the HD-300 kit. Note that the extension pieces are not included.

At the time, they didn't not have pictures of the HD-300, so they had to send me the extension pieces as it was stated in the instruction to use it if needed and its was not optional pieces. Now they have pictures of the part so there is no question on what's included. I found it a tad too long with the extension and caused the hood a bit higher then the fender. Without the extension, it hood line up just fine.