Was going to say.......different transmission.

You are right...sorry....

It's all good info for the next guys.

14 minutes ago, Zed Head said:

It's all good info for the next guys.

So let me get this straight,  based on the tech article link you posted, I can use a later 71C out of one of the other cars or a truck even. Swap the front case and for the most part that will work? No input shaft problems? Sounds like shifter holes and the reverse boss can be a problem maybe?

Yes, apparently.  The most common "71C" source is from a 240SX.  But the 300ZX is possible also.  Somewhere over the years they beefed up the gears in the 71C's, and they also added synchros.  The later models have double synchros on 2nd and 3rd and a reverse synchro. 

I have one in the garage that I did and EuroDat has a 71C swap done also, I believe.  The propeller shaft needs to be shorter, but it's been found that the very early 240Z shafts will work.

Here's a  couple of links showing what needs to be done.  I swapped the countershaft bearing on mine, to avoid the cost of boring out the case.

http://zhome.com/ZCMnL/tech/240SX5spd/transmission.htm

https://www.motortopia.com/cars/1973-datsun-240z-11118/car-pictures/240sx-transmission-swap-14041/DSC04293JPG_Thumbnail1.jpg-266482