These Plastic Speaker Spacers make it a breeze to replace your factory speakers.

Made from Hard plastic, with predrilled holes for you new speakers

The speaker Spacers come as a pair 

To Suit 130mm Speakers - Rear Side Shelf

This product is known to work in the following vehicles:
Holden Barina 1994-2000 SB
Holden Barina 2001-2005 XC