sick620

Yes it will convert the L series transmission to Z series..... BUT....

1/ The D21 transmission has a 62mm counter bearing where the L series used a 56mm bearing. You will need to pull the D2 bearing off the end of the counter shaft and press a new 56mm bearing on.

2/ The D21 1st/2nd shift rod, that's the top one of the 3, is 16mm while the L series front case hole for it is 14mm so that needs to be drilled out so it will fit.

3/ The D21 counter gears are wider and the very front one behind the counter bearing will rub against the L series front case. So some milling of the L series front case will be needed for clearance to thin it out to 0.48". If having this done at a shop get the counter bearing hole enlarged to 62mm and you van use the better and larger D21 bearing.

Machined L series case to allow 71C counter clearance.

Another possibility is to get the Z series front case from a pre '86.5 engine before they changed from 71B to 71C transmissions with the wider gears. From '85 on the larger 62mm counter bearing was used and perhaps the larger shift rod but easy fix. The transmission front cases to look for are...

'80-'83 S110 200sx

'81 and up 720 gas engine.