Having sat in the back with blocks of wood I worked out where my footrests were going and about what size. The next step was to fabricate them from a couple of blocks of foam as you see all done in Pic 1.
Pic 2 is just glassing them with two plys of BID and some peel ply.
Pic 3 is my approach to doing the ends. As I have sharp corners it is easy to use flox corners and just have flat glass here. It gives a nice result.