Manual transmission makes rattle noise when let off gas. PLEASE HELP!

2002 Tacoma 3.4 4x4
Manual swap r150f manual trans

Whenever I let off my gas pedal there is kind of a soft rattle noise and it gets louder the higher rpms. and I believe its coming from my trans. I read that it might be a loose heat shield but i checked and thats not the case. The rattle noise slows down as my truck is slowing down as well. It doesnt make a noise when im in neutral or idling. The rattle also goes away when i barely have my foot on the pedal so Ive just been having my foot barely press on the gas so i dont hear the noise. I was thinking since i dont have sound deadening and a shift boot that then its just the normal sound. Please let me know anything is appreciated.

Uploaded the video on reddit because it wouldn't let me upload it here. link below vvvvvv

https://www.reddit.com/r/Tacomaworld/s/O66a515Njz