One warning to anyone who tries to shift manually:
Be VERY CAREFUL not to push the shifter into neutral!
There is nothing on the stock shifter that limits you from pushing the shifter forward into neutral. You dont even need to push in the thumb button!
Here is what I did:
I took the center console out so that I could see the stock shifter assembly. If you look closely, the thumb button on the shifter handle is connected to a "rod" that moves up and down on a track that looks like a staircase. You can see that the shifter can not be pulled to a lower gear without the thumb button being pressed because the "rod" would hit the lower gear's step (it acts like a wall). So what I did was I took a Dremel tool and ground the 3rd gear step on the track down about 1/8th inch. At the end of the 3rd gear step right before the 4th gear step, I left a small "wall" which would prevent the shifter from being accidentally pushed forward into 4th gear (or more importantly, neutral). Now, when my car is 3rd gear, I MUST push the thumb button on the shifter handle in, so the rod will not hit the wall, then I can push the shifter forward to OD.
If I want to manually shift the 2-3 shift, I can push the shifter forward into 3rd and the shifter will stop by itself because the "rod" connected to the thumb button on the handle hits the "wall" I made on the track of the shifter.
I hope this makes sense. I wish I would have took pictures of this. But if you have seen the shifter assembly, then you might know what I was referring to.