I have the Pioneer P2300 in my 2000 Sierra. For the price, that thing is awesome. I bought an install kit for and 03-07, the models with the double radios. I attached some small would blocks where the stock radio slides into place, and then screwed the install kit into the wood blocks to retain it. The only other "major" modification I had to do was openning up the hole for the radio. I just had to cut and trim the top of the hole about 1/8 of an inch.