zachosz wrote:i remember someone saying that any Nissan transmission will fit if you swap the bellhousings, but i'm not sure on the validity of this
Not any. The KA, SR, CA, RB20, and VG30E all use the same transmission, but with different bellhousings, so these will all swap. However, the 6spd units are a different transmission entirely, so the bellhousing swap is only the first obstacle, even if it bolts up, the driveshaft and diff are different also. HKS and Greddy also make 6 spd units, but they are SR fitments and are built with different bellhousing mountings, making them fit SRs only. Quaiffe makes a 6 spd straight-cut gear unit for the KA, but it's over 8 grand IIRC.