After much rumination and planning I finally got started on the styrene body frame.
I had printed out the plans at work off of our old wide format onto some plain HP paper that I bought. I Spray-mounted them onto the sheet styrene and sintra and made all of the straight cuts during my lunch hours.
I used two Dremel circle cutters that I jury-rigged together to allow me to cut the 18" circles. While I had it out, I also made the circle cuts for the leg pieces and for the shoulder hubs. Also used to drill press to put the holes into the shoulder hub pieces.