hey guys i am a proud new owner of a b 210 datsun well iam in the processof trying to rebuild the gearbox because its been pissing gear oil out of it at idle anyways i started to tear down the box but ihave run into some trouble the only thhe that has stop me from removing the outer casing is the piece where the shifter connects to the main selector fork i have removed the locking pin but the shifter housing only moves along a grove part wy and it wont move any further up i have look to see if its being held by a pin or clip but i cant see any can any of you guys give me any ideas well thanks

If I follow you correctly, your trying to remove the tailshaft housing from the intermediate case???
If so, then the shift lever yoke needs to be rotated to the right (If I remember) to disengage the shift link where it engages the 3 shift rods. Then the tail housing can be slid off leaving the main case, intermediate case and output shaft. The main case slips off next.