2003 Envoy - Can I add Navigation??

I have a 2003 Envoy SLE and I would like to add a Navigation system. I found the GM part number 15204335 which has a BOSE system. I do not think I have a BOSE system in my Envoy now and I was wondering if the GM Navigation system will work in my Envoy without having a BOSE system. If not can I add the BOSE amp to my Envoy? Thanks