Not that big a project. At one time it was very common to replace the cylinders of "cheap surplus" Model 1917's with .45 Colt cylinders. Other than replacing the cylinder (not as easy in a Colt as in an S&W, but doable), the only other change needed is to modify the cylinder stop (the part that keeps the cylinder from moving backward when open) for the longer cylinder. It is that detail that prevents having two sets of cranes and cylinders for an easy swap.
Jim