I have a Jeep Grand Cherokee, and I want to put a new stereo in:

http://www.amazon.com/gp/product/B001PL5STG/ref=olp_product_details?ie=UTF8&me=&seller=

but I'm not sure what I'm doing and I'm not paying $50 to have it done on top of money I'll already be spending. I can't find an instillation kit cause its square not round like the newer 00' radios, is this one right?

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=120633176598&rvr_id=15 4963665537&crlp=1_263602_304642&UA=WXF%3F&GUID=ab3 63bdb12a0a04bd373af63fffeec6e&itemid=120633176598& ff4=263602_304642

any other help would be great, I just want to make sure its possible to get one