The pieces are already cut so no need to add fusible now. Place on the block and stitch down. You can use a dab of school glue or a glue stick to hold in place first. If you have a copier, put the fabric shapes on the copier and shrink it down some. Cut out the shape and trace onto the fusible.
Have you seen the product called misty fuse? It is lightweight and you can re-position the piece until the final iron down. I'm not sure how the cost compares though.
https://www.youtube.com/watch?v=ecCPAjSJM78