jbodak

I recently purchased from CJ Pony Parts a round rally shift **** and shift boot retainer for my 2011 Mustang GT/CS. Looks great and I love it. I installed it following the instructions provided by their video on their website. However, at high revs while accelerating pretty aggressively in 1st and 2nd gear, I hear a rattle in the shifter that wasn't there with the stock shift ****. I watched the installation video again and in the video, it looks like he may have tightened it harder than what I did. Could that possibly be what's causing the rattle? The rattle sounds like a plastic piece vibrating against something. I tried putting a little bit of cotton in the stock plastic "cup" that holds the shift boot thinking that maybe the bottom of the new shift boot retainer was vibrating against the stock plastic "cup" but it stills rattles. Everything seems to be on tight. Anybody experience this? Thanks