If you're talking about the "iPod" module, it's under the driver's seat.
You may be able to raise the seat high enough to remove the black plastic cover (unscrew the two plastic crosshead pins) to reveal the cavity under the seat containing the ACM, which is mounted above the camera module (if fitted).
You'll see it's attached with two 10mm nuts on bracket mounted studs.
If you can't raise the seat high enough you may have to remove the four 10mm headed bolts which mount the seat to the floor and "tip" the seat backwards to gain access to the area.
Rob