Good to see there are still some options for this issue, I'm sure they are not economical or make much sense compared to an aftermarket HU replacement.
To all wishing to keep a factory radio, from old models, without aux and a CD player that at least could play MP3 files.
The only solution is burn 80 min cd's in a cd format and enjoy the 6 cd changer.
All can can say is good luck, you can throw money at an old outdated radio installing iPod adapters or external modules just to have functionality with some issues besides sound quality.
You will miss, BT streaming, HD radio and USB option not only for mpt3 players but also a simple flash drive for $14 you can have 16gb or up to 32 gb of digital music playback all with display of titles and artist's names.
The CD players also support mpt3 or mpt4 Apple playback of files up to 320kb, meaning up to 70 songs per CD or more, no need for a cd changer.
Might as well buy a new truck assuming the new models offer all those features and the latest technology without limitations.
Dual is a brand that has come a long way in quality with their head units, 2 nice things about many of these units, the phone mirror image screen, and more important, the steering wheel control compatibility built in, besides the remote control included with most aftermarket head units.