Here's her email to me.
"No, we do not allow that install. When a parent calls with a Tacoma, here's my response:
Its rear seat is simply not compatible. Car seats are designed for and crash tested on a cushioned vehicle seat with a slope of 15 degrees from horizontal, as outlined in Federal Motor Vehicle Safety Standard 213.
We do not recommend installing the car seat in the back of that vehicle. I recommend that the vehicle only be used as a last resort. If it must be used, install the car seat in the front seat with the front seat moved all the way back and the air bag turned OFF. It is imperative that the air bag is turned OFF, so it will not injure the child.
Feel free to email me again if you have any questions or would like to discuss this further.
That seat is simply too hard and flat. No car seat is tested that way."
With a base the Keyfit was overreclined. So I was emailing her about a baseless install, which had less than 1" of movement and the appropriate angle for a newborn.
Wendy