I have recently acquired a 75 HP Chrysler outboard model #757H8D Ser. 3449. Looking to find out what year it is and where I can get an impeller (part number too). I would also appreciate a recommendation for a good manual for this motor. Motor has been sitting for 5 years but starts right up and pumps water but have been reading some of the posts and looks like the general consensus is change the impeller. Thanks for any advice.