using a s1 jdm b16 tranny for my turbo jdm gsr DA

hey everyone. i have a jdm gsr swapped into my DA and its turboed. my ls is grinding gears now and im bout to buy a b16 s1 tranny and im gonna put a lsd in it. do u guys think this will be too short of a tranny, im gonna eventually be upgrading pistons, rods and different turbokit. just wondering if u guys think the jdm s1 b16 tranny will be too short. i mean i like the long gears of the ls but im sick and tired of them grinding on me cuase im revving to 8200 rpms so i need somethin thats gonna be able to take the revs. i was thinkin about putting the ls fifth gear in it as well to help out on long trips. is there another tranny i can get that would take my high revs and be a little shorter than the ls tranny but also be a little longer than a jdm s1 b16 tranny??? thanks