Ive seen some pics of this done in the past from ramdom photos from a japanese owner.
Would anyone know which coil-over replacements where used?

This would save at least 15kg of the front end, not to mention a replacement for the
no longer available factory items.

How would it save weight ?
Do you think the leaf is that heavy ?
Especially after you fab up brackets , coils, beafier shocks

I'm doing it (eventually).... haven't weighed anything yet though
But my front is heavier anyway with new brakes and modified upper arms , swaybar , etc

I guess the cross member then becomes just a cross member (and not a spring housing), meaning it can be significantly altered to take a fatter/taller/bigger donk.

But yeah not sure what all the weight saving is about. I want more weight in my 1000 not less. Carrying all those flanges today actually bettered the ride. When I go over some bumpy parts of the road the car sorta rides like a fricken boat (probably shyte shockies though) but when the weight was on, I was driving with a little more belief that I was in a car not a tinny.....

Back to the question...... yeah I can't answer that.

Perhaps zap Mike or Endo-san a note? the bpro coupe runs coils', pretty sure it does anyway.

Bpro coupe ran 1200 struts grafted in from memory

Two questions regarding structural integrity:
A: would/could the upper shock mounts have to be modified for the extra stress? (Keeping in mind you are taking stress from one to a completely different area)
B:Could the Xmember itself actually be made weaker by the removal of the transverse leaf?

Josh can you find the ones with the coil-overs only?
I honestly would never go as far as putting struts in a B10.
It looks like the engine sits lower in that pic (must have
modded the crossmember at the base also?)

Crossmember will be as strong (will be stronger with no upwards force)
Shocker mounts are overly up to the task (endo-san I think proved it)
transverse spring is very heavy when I picked it up I thought to myself
what the hell now I see why serious owners want it gone.
Lates coilovers are very lightweight and no more than 3-5 kilos.
I will allow a custom lower crossmember or angled rectangular tubed pipe
to rid the original crossmember that sits at the point of depth of the
A series bulge meaning better clearance for taller motors with winged sumps
especially if angling an A series 15-20 degrees for better inlet/exhaust
manifolds as done by corolla K-series addicts.
When Simon makes my custom bellhousing he can angle the engine keeping
box straight in original position so the A will sit like an L series.
Imagine how easier sidedraft setups, headers and superchargers will be :)

Some of that upwards force is directed to the centre of the Xmember via the leaf, as opposed to all the force on its extremities without, wouldn't this require some additional bracing/xmember support?
...but if your'e going to modify the Xmember to suit, I guess it dont matter

That reminds me, the angle of the carb flange is different on the A12 compare to the A10. Those Datsun engineers used every trick in the book.