hi guys, nice to meet you all! I'm new to this sport. all my life i'v wanted one of these stand up jet skis and I finally picked one up. its a 1985 js440 but it has a bad crank bearing, I was hoping you guys could help me out. I am wondering what is involved in swapping the newer js550 or 650 in place of the old motor because I saw one on ebay for cheap. any ideas or advice?