Hi i recognise that new speaker t bar cover
The speaker xqm number,one part number simply supersedes the other. The speaker box does fit all MGF & MGTF models.
Changing the rear t bulk head cover for speaker grilles involves also removing the seats to unbolt the seatbelt from the seat itself.
The seat belts run through the t bar cover and must be pulled through the rear on removal of your old one and then pushed through if you opt for the speaker grille version.
Rear speakers was only introduced from MGR on the 2000 MY MGF onwards so you will need to factor in for additional wiring.