I just finished the rear deck speakers and the door speakers. The door speakers were actually easier (I didn't expect that). I went with JBL GT7-6 from Crutchfield (no, I don't work for them, but they deserve any business they get). They fit perfectly using the Metra adapters they send you.
Here are the issues I ran into.
For the rear:
1. Instructions say to remove the rear seat. I'm not convinced that's necessary, but if you do, when you put the seat backs down, they rest on metal. You could tear the upholstery if you don't put padding in between and put weight on it.
2. I bought the PVC adapters. My speakers (Infinity) were too large, so I had to dremel the inside hole to make it bigger. In retrospect, I could have done that BEFORE I had my car all apart.
3. I bought sound deadening mat, then didn't put it in. It just seemed like more work than necessary.
For the front
1 Nearly impossible to unplug the wiring harness for the power door locks. Prepare some method of supporting the door innards if you're not able to do so.
2 Watch where the "pop" rivets go. Some may stay in the door. They need to be removed from the door and put back into the (plastic) door innards before snapping everything back together.
3 Test fit the speakers in the adapters. Snap off the tabs of the adapters as needed. Wire adapter is fed through hole on perimeter of adapter, so locate adapter so that this hole is in close proximity to the plug on the car.
Hope this helps someone.