i don't believe there is any mix and match possible that makes a usable transmission ratio wise. the gen 2 gears are only a touch longer than gen 1 so not really worth swapping just for the slightly longer gears. you can use a gearset from a diesel mazda 3 but that requires machining on the input shaft to connect to our motors. your last choice is that SpeedPerformance had at one time custom made final drive shafts, i dont know if they still make it or if you would need to look for one second hand. that said, the consensus from folks that got the longer gears was that you really needed to be 500+ hp for it to make sense