I am somewhat new to creating posts so here goes. I have 2009 M35 S and my propeller shaft u joints finally gave out I had no luck at the dealership let alone my local autozone and orielys and any junkyard for finding a replacement. So I found a 2010 G37 sedan and took out the propshaft. Now I am going to attempt to either cut the end off of the G37 shaft and cut the end of my props haft and have a shop weld it on to the newer shaft or pull the companion flange off the G37 and swap it with my differential companion flange , anybody have any thoughts?????

Swapping the differential flange is probably the easiest by far. Ive done that twice on my differential side and it isnt any big deal. I havent really looked at the driveshaft end flange but it shouldnt be too difficult to swap the flange. If it is, maybe you can find a used G37 differential for cheap and swap that into your car as well? That would match up correctly and give you a better acceleration gear ratio too.