To purchase https://www.codythecarguy.com/store/product/ford-7-3-nozzles/
I broke down a injector so you can see the working parts and how the new nozzle goes on it. Also o-rings replacement and how the solenoid goes on it. These injectors have a mini p&b in them also known as the plunger that moves the fuel through the metering valve
https://www.codythecarguy.com/store/product/7-3-injector/
https://www.codythecarguy.com/store/product/ford-7-3-nozzles/
SAE-AISI carbon and alloy steel designation numbers explained and visualized.
My last Fe amount should read 98.5kg.