Is the thread size/pitch the same as the DC2-R ****?

I have a friend who installing a SR20DET in his 240SX https://honda-tech.com/zerothread?id=94765

His swap did not come with a **** and he likes mine a lot.
Before you ask, his car has a 6-speed.

The DC2-R **** won't fit his shift arm.. so it will have to be machined. I just wanted to know if the threads were different.

Is there a jam nut on the underside (like the DC-2)?

Will