RC-Monster Battery Tray

[FG101C]

Hi guys, this may be a stupid question to some. I just got my RC-Monster battery tray. It comes with four small black screws, four larger but short stainless screws and a piece of plastic sheet which I understand is to space for the mudguard. Now I have'nt really sat down and looked at this but I'm not seeing how it mounts to the chassis. I take it some drilling is involved, but the screws seem too short to mount this securly enough to hold a 4s LiPo in place. Also not sure what screws do what. This is going in a Losi 8-T.

Thanks for any help or advice on this.