89 stereo ?

[super10]

What's up guys. As you might know I am new here. I am a regular member on the impalassforum but thats another story. I have searched around looking for a place where I can buy a install kit for my 89 chevy ck1500. The one that installs in the center of the dash where the tape player is. Any one found a good place for these? Also I know that the display unit is only a display and the real head unit is under the dash, where exactly? Also I have found the wiring diagram (http://www.installdr.com/Harnesses/GM-Wiring.pdf) here, is that from the display unit wiring or the head unit? My radio in my truck craks, pops and basicly get on my nurves so I am upgrading. Thanks in advance for your help guys. Oh yea...

Kevin