I have alpha one mercruiser and it will not shift in revese and forward. I can get one or the other but not both. Tried every way possible to adjust cable with no luck. I can shift it into gear and get out of boat and turn shift lever on outdrive with screwdriver and I just have to move it a tiny bit to get it to take gear but can not get it to engauge without screwdriver. I was told that it sounded like the lower shift cable needs replaced. I was wondering if this sounds like my only choice or any other tricks available. If I do need to replace is this a major job that I should leave to professionals or can someone that is "car" mechanically inclined be able to do this. Is it fairly easy or a major surgery. I have had the lower unit off twice already to change engine and then again for water pump. Any help would be great.