Q.Pruning silk floss tree
My silk floss tree is at least 40 feet high with a spread of at least that much. How should it be pruned?
I would suggest you consult a qualified Arborist to tackle pruning a rare tree.
My research show pruning is only needed if you need to increase air circulation and you can remove up to 25 percent of the canopy. Pruning will result in loss of flowers for a few years.
https://www.gardeningknowhow.com/ornamental/trees/silk-floss/floss-silk-tree-planting.htm
http://hort.ifas.ufl.edu/database/documents/pdf/tree_fact_sheets/chospea.pdf