The props, if as supplied, will probably be the right size and shape. When I did my Lindberg tug many years ago, I used the kit prop but found that it was more inclined to act as a sideways paddle. Since I, too, had epoxied it to the shaft, I wound up re-profiling the edges the hard way - in situ, using a sanding stick. Took time, but the results were worth the effort.
On my Tuna boat, I just used the kit prop, but a few years down the line I managed to break it and replaced it with a home made one according to the tugboatjoe method, soldered to the shaft. Something like a Fletcher, with its higher performance, does deserve better, though.