No, you can't put 350z R230 gears into an R200. Yes, you can swap any R200 gears into any other R200, Q45 or whatever.
sidenote, if you have an s14 subframe in your car you can swap a 350z R230 with only conversion bushings. An auto trans 350z R230 will get your 1st-5th the same as they were with stock transmission & diff, 6th gear will be another overdrive. That's what I plan on doing whenever I put the CD in my car.
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