so to digress from the topic, if doing the borgwarner into a 1200, will the 120y tailshaft be the right length for the 1200 from the 120Y?

I had the same problem . I just did what you said you didn't want to do. But I'm fortunate enough that I'm a mechanic sos I did the yoke swap myself

It's likely that the Aussie model 120Y had a BorgWarner diff in it. The JDM H150 diff that you have in the Sunny won't bolt up to the 120Y drive shaft. Best option is to get a manual drive shaft out of a Sunny. If that is not possible then it's a good chance the manual shafts for the 1200's 145 diff may fit. Maybe someone else can clarify that?

The girlfriend (a.k.a Datsunny80) and I undertook a manual conversion amongst other thing on her B310. The car is an A12 powered factory Auto and we collected all the goods for the conversion, most of the stuff coming from a wrecker's 120Y.

Now we have a problem that the manual tailshaft, which is noticably thicker has a larger diameter hole pattern on the yoke for the diff side, meaning it won't bolt onto the Auto diff. The thing is the tailshaft is also from the 120Y which I was under the impression was the same running gear as the Sunny.

Does this mean that they run a different diff on the manuals and if so, does anyone know of a tailshaft that will match the Jap end "Auto" diff with a 120Y 4-speed? It's just that we got the tailshaft for free and it'll cost $150 to get a hybrid tailshaft made (yoke swap). We can get ny tailshaft swapped for us at no cost from the wrecker.

Forgive me I'm new to all of this, first Datsun, first RWD car I've dealt with.