I am going to pull out my rotor in my R62 combine and fix it. I am planning to put F2 rasp bars in it. I have an old F3 that has been stripped of many parts, the cylinder is still in it and those bars are good, can I use them for the rasp bars or are the same thing. The pictures in the mods section show them but they look narrower than what I have or do I use what I call concave bars? I feel like is a dumb question, I should know the difference but I want to do this right and before I do a lot of work on the combine I want to make sure that I have the right parts. Thanks for any advice you can give me John