Thanks IH2LOSE. I didn't include the CD. Did you buy your dual front speaker from Custom Audio Sound? i.e. I talked with them briefly last fall before I stored the Vette, and they did point out i should check the speaker Wattage. I haven't done this yet because it only happens when I turn the key off with the motor running. I did check the ground. This helped with the radio speaker sound, but didn't seem to reduce the blast of static, or snap, as you said but it is still pretty loud.
I bought mine from Valley Vette, Appleton, WI. I was actually able to install it behind the glove compartment beside the tuning panel, by slightly modifying the bracket. If I ever learn this computer stuff, I can send pics if someone is interested. Like you, all I have to do is replace the glove compartment liner to turn everthing back to original, and reconnect the speaker to the original.
FYI, After repair several years ago by an authorized Delta shop, my original has good sound, and works pretty well, but I lose the signal frequently then it comes back on a little further down the road. See ya