Yes those are the only locations. 6 speakers in total. No tweeters at all. There are 6.5's in the rear doors, 6x9's in the front doors and 2.75" speakers in the dash. The dash speakers and the front door speakers share the same channels.
There are plenty of options for the doors including adapters to mount 6.5's in the front doors. There are also harness adapters for the door speakers locations. I did not find adapters for the dash speakers but that became moot anyway once I amplified each speaker separately which required running wires to the dash. There are also very few speakers that will directly fit in the dash locations. Morel, Audiofrog, Kenwood and possibly Infinity that I am aware of. There could be more options. If you go with actual tweeters then a adapter plate or bracket will be necessary.
This is the dash speaker and it's opening. This is the opening with the piller trim reinstalled. If you are willing to cut the dash you can fit larger speakers but as it sits there is only 3.2" of room in there.