Hey all I'm looking for some advice my son and I are replacing his original 2006 R50 motor with a used 2004 R50 motor we found with lower mileage 2004 R50. The 06 is a manual 5 speed and the 04 was an auto matic. Everything lines up fine between both new and old tranny housing not problem. However the fly wheels are different the one on the 06 manual is thicker but seems to be the same diameter etc. so I wondering if we should leave the fly wheel on the 04 motor that had and auto trans or take the fly wheel off the 06 manual trans motor and put it on the 04 motor now? My instinct tells the fly wheel is weighted for the manual tranny so move it over with it. But just wanted to be sure any help would be super appreciated. THANKS!