Installation is pretty simple. I put mine in a nice smooth vise(no cross hatches for grip) put injector in vise get nice and tight, get proper 12 point box wrench with a long shank for the most leverage, dont try to reef on it all at once, take firm taps with your hand to slowly break them loose, spin off head, tip will slide out(dont loose metering rod, will stay with each tip, new ones have them already)might have to clean a little to get them out, clean head up real good, install new tip in head and line up small pin on nozzle to injector body and make sure fuel hole is also in right location, install and tighten. Best idea to take and get popped when your done, i did mine and only one was off by 20 psi.
hope i explained it good enough, its pretty straight forward, just be clean and all will go smooth. DD