Can I drill into the carpet? (1 1/2 inch screws)

[ituner-HF]

I need to secure a power amplifier (RF amplifier) and other electronics under the rear seats, can I do so using some 1 1/2" self tapping screws? I probed the carpet with a needle and it seems to go in, there is some sort of semi-soft material under (foam?). From the pictures I see, there is quite a lot of room (few inches) in between the carpet and the HV battery pack, here are some pictures. with and without carpet installed.... Thanks!