I purchased a 1994 Carver 30' Aft cabin with 2 Crusader 350xl engines. This vessel size and the inboards are new to me, outboards up to this point. I have been researching the repowering options and spoke to numerous companies that offer new or remanufactured drop in/turnkey. One company tells me that all of the 350hp,5.7,454 between 1987-1996 are identical other than exchanging manifolds that convert it to a mercruiser, volvo-penta etc.Is this valid? What is the difference in the term remanufactured vs. new? Thank You