Speaker size and suggestions
 

I have a 2008 Civic EX-L sedan and it has the stock six speaker layout. I want to do a speaker upgrade to the rear deck and front door speakers. I'm getting mixed signals on what the actual size is and if adapter rings are needed. I would like to lean towards 6 1/2" instead of 5 1/4" if that is an option. Can anyone confirm the size of each location and suggest any models/manufacturers that have worked out? I'm just looking for a speaker swap out without rebuilding everything. Thanks.