Hello, Sorry you're having problems. Yes there is a specific "Pioneer Radio Removal Tool" needed to pull the chassis out of the radio sleeve. I am pulling up a link to this part now for you.
These tools, or "Keys" as they'll generally called, are available at the link below for $6 for the pair needed to remove the radio:
There may be a plastic bezel around the face of the radio (depends on the installation method used) that you will need to "pop off" in order to access the key slots which are on the sides, about halfway down on the radio.
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