Injector Question - What's missing?

[Kobe Diesel]

Im getting ready to install 19# Mustang injectors on the M20. Im looking at the injectors and trying to figure out what's missing, if anything.
For reference, Des III, #'s on the injector "F6VE A5A" & "0 260 155 710"

[ericcamaro]

looks like it could use a spacer between the bottom o ring and the injector body. it will help the injector seal but you will have to remove the caps and they like to break. I dont have much experience with those injectors though. mostly the older bosche design.