Seat installation help

Some pictures. 

As Matt mentioned, on some, the seat back upholstery has the foam inserted in it, then the the seat back upholstery is laced around it circumference to the frame

the F-1 I work on has the same seat as my G model, the seat back is removable and  is hinged at the bottom and held in place with 3 bolts or clevis pins. The earlier models the seat back is part of the airframe and seatback cushion is laced in place,

Hi i have a Forney F1 and live in Australia. When i purchased the aircraft it had C172 rear seats installed which weren't installed that well and i didn't like.
I purchased second hand seat frame and seat from Vern. There are not many Ercoupes in Australia so i can't look at another to verify the correct seat installation. And, what is the correct process for lacing up the back rest, before or after the frame install? And what foam is installed in the back rest the back rest currently doesn't have any foam installed. Any assistance with pics or articals would be appreciated.

Thanks Rob