Sorry, 1/8 BSP, my brain was not in gear.
The "as drawn" thread is 10mm x 28, this is a little bigger than 1/8 BSP at 9.73 mm. About 10 thou different.
That's the size the female thread in your suspension tool should be.
But of course the small difference has tempted people into endless bodges over the years, both on tool and damper rod.
Consortium has new nuts, and one would hope any new parts are to the original drawings. I am sure the New Vintage Parts damper rods would be.
We have had a special tap made, but I think it is loaned to a supplier currently making new suspension compressors. I am going there and can recover it to lend you.