guys, need your advice on this.

1) Im driving a manual Kancil & kinda interested to buy a FM Modulator to hear MP3 from my thumb drive since my CD player doesn't support MP3. But the problem is I dont know what's the real size of this FM modulator & after plugging in my thumb drive, I worry I might not be able to shift to the third & fifth gear as Kancil is a very small car.

2) Where to buy FM Modulator & how much?

Thanks.