Speakers in center console question

[Chiefdan]

I have a '67 Shortbox stepside with the bench seat. I have a Sony AM/FM/CD radio ( dash has been cut by po). I have two 4" speakers under the dash one on each side. The rear speakers are about 8" oval and are both behind the seat in the passenger side corner. I am not a true audiophile but I think the sound is terrible. I am thinking of getting one of the floor consoles with the cup holders advertised on this site and installing 6" speakers one on each side. Do you think this will improve my sound? Also looking into replacing the radio with something with bluetooth and any recommendations along that line would be appreciated also. Thanks guys.