Dell OptiPlex 9020 sff thin metal part on expansion slots.

Hi

I have tried fitting a low profile firewire expansion card to my OptiPlex 9020 sff computer.

when I put the card in it would not sit fully in, on closer inspection the thin metal shield or

whatever it is had come away at the bottom and I had to remove it before the card would

sit properly. my question is do I need this expansion slot shield that the plate sits on is very

thin and flimsy anyway.