Hay Misfit47,
Call Robart...I believe they had a set of retracts for the Royal B-17. I have the kit too...with the cocpit kit they sold. I have seen the model fly, and it does fly well and it looks great. There have been companies that sold fiberglass cowls for the kit in the past...but I don't know of any now. You may want to call around and see what is available.
Soft Landings always,
Bobby of Maui