So here I go I bought some cans from bullet lines and did not realize that my polk momo650 will not fit I am trying to find some one who is or no's a machine shop to make me some adapter rings so I can stay with the same speakers. I live in oklahoma please, any help would be appreciated.
http://www.bulletlines.com/servlet/the-57/Wakeboard-Tower-Speakers%2C-Wakeboard/Detail?sfs=17f0a1a9 
Driver Cut-out Diameter 5" (12.70cm)
http://www.polkaudio.com/caraudio/specs/speakers/6-1-2/mmc650/
Threaded Mode