So which one is supposed to be used for the GLX-Redline MTL or Redline MT-90? I read somewhere that the right one works great, but the other is not made for VR6 cars and should be avoided. However, I'm not sure which is which. Also, pardon my lack of mechanical knowledge, but if I decide to add the short shift kit, do I need to replace the tranny fluid as well? Thanks for any advice, Kevin