can someone please help me im trying to install a new fuel pressure regulator but i cant get the clip to fasten the fuel pressure regulator down

i have a ford falcon xr6 ba 2004 Ive managed to remove the old one which was very seized but i cant install the new one it doesn't have a cir clip instead it has a a v shape Retainer Clip but i cant push the regulator down hard enough Ive lubricated the seals with motor oil but it still wont push down

i have depressurized the fuel system by removing the fuel pump relay and trying to start the car for 10 seconds so i know it is not pressurized


also i have compared my new one to my old FPR its exactly the same i have also tried to reinstall my old one im having the same trouble

this is the clip i was talking about
https://ibb.co/JvLXHCp

this is the FPR that my car has
https://ibb.co/rvk7zyS

and this is what im trying to do but it wont fit
https://ibb.co/MBBXCjb

When trying to push the regulator down into place, apply even pressure across the top of the regulator. Use your hands or a tool to press down evenly on the top of the regulator while guiding it into the fuel rail.
geometry dash