stereo slides out of dash

[Industro666]

i bought a new pioneer stereo online to put in my truck i have it installed right with the wiring and it works great but when im driving down the road it slowly slides out and i have to keep pushing it back in. is there something i didn't do or some kit im supposed to buy so it will stay in? im new to this and i'd like it to stay not just because it's annoying but because it's a theft risk. i have the 1994 dash that's square with a single din slot.
i dont have a camera and my cell wont send pics anymore but this is the dash im talking about and i used to have that kind of stereo now i have the pioneer 3100
http://upload.wikimedia.org/wikipedia/en/3/3f/FordRangerDash.jpg
any help is appreciated.

 

[RangerFabWorks]

Ok the metal cage that's around the stereo slides off. Then you stick that in the dash. You will notice metal tangs that are cut into the cage. Bend those up so they lock into the dash. Then slide the radio into the cage. There's your problem

 

[Industro666]

Ok the metal cage that's around the stereo slides off. Then you stick that in the dash. You will notice metal tangs that are cut into the cage. Bend those up so they lock into the dash. Then slide the radio into the cage. There's your problem

how hard will it be to get it back out if i want to change it again?

 

[RangerFabWorks]

There should have been tools that came with the radio. Remove the trim ring and slide the tools in the slots on the sides of the radio. Then slide the radio out. Then just pry those taps down and you're ready to go

 

[RangerFabWorks]

Check out this video on YouTube:

http://www.youtube.com/watch?v=Anl4_dJEaLY&feature=youtube_gdata