[sethkestenbaum]

The front backrest is secured (at least on the 1929) with two bolts that are accessed where your feet would kick the front seat if you were sitting in the back seat. These bolts each hold a bracket in place. If you remove the bolts (on my car they were rusted out and I had to file them down to remove them) you can then grab the the bottom of the backrest and lift forward and up. This is how it seems to be put together in my 1929 Phaeton. I haven't tried to do this on the back seat. I hope this helps.