Just purchased a used 1997 800LXS w/ 150XR6. When I get the boat up around 60 mph it starts to "walk" from side to side. I have tried adjusting the trim up and down and centering the weight but none of this seems to help. I've been wondering if a jack plate would help solve this problem or if its something else. If anyone has had this problem or can give some advice I would appreciate it.