We will include a set of inserts with a pre-cut 4.5" hole for installing a 5.25" speaker! Also included will be a postage mailer for you to drop your original inserts in and mail back to us. $10 with any purchase or $20 as a stand alone service.
Due to the limited quantity of the inserts available in GM inventory (basically non-existent nationwide), we are unable to offer this as an option without you agreeing to send us your original inserts in return.