if my car is declared totaled can retrieve the after market stereo if i still hold the title

If a car is declared a total loss due to an accident or event, the insurance company usually will not allow you to remove anything that is currently a part of the vehicle.  You may ask the adjuster for an itemized list of the value of the car and see if it shows the stereo as a part. However, that still does not mean the stereo can be removed.

You can see if the body shop has any issue with you removing the stereo. If they do not, you can go down and see what it might take to remove the stereo. Any serious work would not be a good idea. If you have the original radio/stereo that came in the car, you can take the old stereo and replace it with the original radio. It is unlikely the insurance company will know or care. The final option would be to talk to the adjuster about this. Many times, since the car is a salvage if declared a total, they would not have an issue with removal of the stereo.