Audio Systems: Stock Delco Stereo, delco model, gmc sierra

Question
I have recently purchased a new JVC KD-AR480/KD-G430 Stereo for my 1997 GMC Sierra 4x4. The issue I am having is that I have access to two (2) wiring diagrams for my truck's radio however, my problem is that I don't know if I have an amplifier or not installed. I have two (2) clips on the back of the stereo aside from the radio lead. How do I know which wiring diagram to go with? The Delco model I have is 16213825. I can provide photo's of stereo if you wish.

In addition, is there a way to safely connect the new stereo to the existing wires without cutting out old clip? I may decide to re-install stock stereo if and when I sell.

Thanks in advance.

Answer
yes you can buy a harness to install the radio and not cut the wires  also if you do that they will match the jvc wire colors

and the last thing is that some trucks have a small amplifier under the driver seat if you don't see it it is not there
good luck