Just picked up a 1972 MirroCraft, 14 ft x 63 in aluminum boat. The only gauge on it is a volts gauge. The prop on it is chipped in several spots and has a hair line crack starting on a fin to the base. The prop size is 10 1/4 x 11. I found a 10 3/8 x 12 1/2 off of a Chrysler 35 horse with same...