Injector (nozzle holder nut) thread size?

Hi, can anyone tell me the thread diameter and pitch (circled in the image below), to save me pulling one of my injectors prematurely? I need to find or make a compression test adapter to fit the injector hole in my M4500DT - the injectors (15721-53020) are same as many other models apparently e.g. engine models Z751-B; Z851-B; DH1101-B; D1301-B; V1501-B; V1701-B; S2200; S2600.

Thanks for your help.

Pulled an injector: M24x2.0 mm pitch in case anyone else wants to know in future. I'll post sketches of the dimensions of the adapter and hole in the head later.