'72 C20 - installing grille mounting clips

[540ChevyC20]

Hi team, does anyone have any tricks for installing the white, push-in grille mounting clips? See pic. These are the clips that mount the grille to the grille surround. I bought new ones from LMC Truck and I'm absolutely stumped as to how to get them in - the amount of force needed to get them in is beyond what I can apply with my hands or any tool that will fit in to the available space (at least while the grille and surround are on the truck). Thanks in advance!