I have my radio/CD player in my glove box. Still space for a CD in the box, a garage door opener, a pair of gloves and the tire pressure guage. I didn't want to cut holes anywhere so the speakers I chose come in their own enclosure and I have used a bit of velcro to afix them to the carpet on the back package shelf. Should I have luggage I just unstick them from the velcro and move them to the top of the pile. I can also pull them out for a picnic, etc. Worked well for a good number of years. I'd post a pic, but haven't as yet mastered the art.
Mark