In need of a cylinder head... a GX head would be nice...or a good not cracked head I can rebuild!
I went to the junk yard this weekend and struck out!

Is this an A12 engine? The A14 head is better for street driving than a GX head as it has smaller ports (but still much bigger than A12 head). This is a nice upgrade for A12 if you keep the engine for 4000-6000 RPM operation (for under 4000 RPM, the A12 head is better). You will need A14 oval-port head, intake & exhaust manifold + exhaust pipe stub (3-bolt pipe for A14, 2-bolt for A12).

When fitting A14 head to 1971-1973 A12 engine, drill/grind the oil passage in the head.

Note that there are round-port A14 head which will work too, about the same as A12 heads.

DD how about the pro swirl head for better all round torque cant remember the part number but doesnt it work best for the street due to its supposedly better mid range and economy?

Depends on how high you want to rev the engine. The standard 4-6k rpm like an A12, you should use oval-port heads.

But if you want to short-shift at 3000 rpm, use the round-port or shroud-port (mid-size oval) head.

Would a 81 310 A15 head work on my A12,looks like I have to drill the oil hole and it has round ports.
No part #'s so from what the wiki say's it's a H10 Head.
Should I spend the money to fix it??
What aligns the head to the block? L motor's use a dowel with the head bolt .Do you just use the bolts them self's ?

There are locating plug things on the block. They come out of the block only a couple of mm.

http://datsun1200.com/modules/myalbum/photo.php?lid=2538
Notice on this pic top right and lefthand side of the block there is a couple of small cylinder plugs, they align the head to the block im pretty sure...

1981-1982 USA heads are shroud-port small-ovals. Doesn't matter A12/A14/A15 they are all the same. Canada heads are different.

As already indicated, A14/A15 heads can be used on 1971-1973 A12 engines if the oil passage mod is used. There are no heads unique to A15, all A15s use various A14 heads.

That's what I thought,The L series you have to use those or the valves will hit,I learned the hard way on that one!
But when I disassembled the motor there were none!
How do I get those?
Man I never thought it was going to be this hard to do an A motor!
So what do you do about the water going through the intake manifold?
Block it off with a weld ?

What do you mean? The valves won't hit. The A-series heads are not like the L-series heads.

A-motors are very easy. Just use an A12 head, and you'll be done! Or use a 1975-1979 A14 head, which has no water ports for the intake manifold!