It's been a hell of a long time, but from memory, the E30 disks have an integral bell. The stud pattern is the same, so the disk went over the top of the 1200 hub (it was probably a 120Y strut and hub, they're stronger).
It gave you a 10ish inch disk which just went inside a 13" halliday rim.
There was some fabrication involved to get your favorite willwood caliper to bolt up.
This setup was used to good effect for circuit racing here in NZ...

E30 bimmer discs and wilwood 4 pots

Yep, 1mm piston - valve clearance at assembly just isnt enough, 41mm valves weigh a ton, it's not a 16 valve engine with little light valves. These big old things really move around at speed..
Take the small hit in compression ratio and put deeper pockets in your pistons IMO.
Also, the stock pushrods bend like you wouldn't believe. Put a dial gauge against the side of them sometime... Now think about it all happening at 7000rpm.
Just putting in decent pushrods makes a huge difference in the effective lift at high rpm.

mmm, I'm lucky I have an understanding wife... she justifys it in her own mind by saying 'at least I know where he is, he's in the shed, not down at some pub misbehaving'

Just picked up a 82 S110, Datsun Badged. they only sold em in New Zealand AFAIK, everywhere else they were Nissan Silvias... L18e, auto, disc brake H165 rear end....Pure joy..

Just cut a silvia up, so I'm down to just three, + the 1200 now... not counting the daily drivers....

anyone know what the CG13 Micra engine wieghs off the top of their head...
I could lift the last one of these I had on the garage floor on my own

The clutch was the secret in my case. I ran a similar spec 1300 (107rwhp), a Close Ratio 56 series 4 speed, and a escort diff with 4.7 gears and english LSD.

Once I put the proper nismo sprung centre paddle clutch in it, it was like driving a road car, never slipped, and never broke anything.

man, how many hours work are you going to put in to save $100?
Sometimes it's just not economic to do it yourself!

I do my own...actually, I lie. I give em to my brother who has a press, drop in a tray of beer and he does them. I open the beer, watch, and make sure the beer doesnt evaporate... Works for everybody....

So yep, smack the original collar in three places, really hard with the cold chisel to spread it. It should come off pretty easily after that. Heat the new one up in the oven or similar before you whack it on, and make sure you really seat it down against the bearing...

Beautiful.
If only nissan had also cast the FJ24 in alloy

yeah, FJ in a 1200 is not a nice swap. They're just too heavy.. The A15 will be far more satisfying...not as cool and scary, but quicker and more satisfying....

38102-A 7600

They're the M10x1.25X22mm long one.