Re: Tool to remove seat bolt?
Mission accomplished. Had to remove the four bolts and tilt the seat. Read a suggestion to cover the plastic doorsill to prevent scratching - I did so. HOWEVER, if you are tilting the seat, be very careful of the metal "legs" hitting the center console. I learned the hard way and now have a slight scratch on the gray sidewall of the console. (This is scratch #3 on the whole car.)
I now have a gray washcloth folded and stuffed on the inside between the seat and the console. Good suggestion!
PS - The 4-piece internal star socket was only $7.99 at Autozone and E12 fits the seat bolts.