Here's some pictures of my booster seat and son. This is with the front passenger seat moved forward to the first point that it engages on the track. This leaves enough room for my wife to sit up front, but I would not be able to:
Here it is with the front seat moved all the way back on the track:
You can also see one of the anchor points I used for the "latch" system in this last picture. The other side is attached to the seat belt D ring and there is an "actual" anchor point at the top.
I am thinking that I am going to cut a piece of 1/2" ply wood to fit the base of this car seat, to make it a bit more stable and so the front of the car seat is sitting on something instead of just hanging off the truck seat like that.
Here is the link to this car seat, but it won't work for a newborn:
and here's the small one I was talking about before, which will work for a newborn, but it's not the type that you can take out of the car with you. This one would probably work great in the front seat of the tacoma though: