Car Stereos: rear speaker installation, chevy montecarlo, montecarlo ss

Question
Hi, i have a 1986 chevy MonteCarlo SS, Id like to install 6"x9" speakers in the rear, however it is made to take  5"x7" speakers. could you tell me where I can purchase at a store or online , an adapter to convert my vehicle from a 5"x7" to a 6"x9"? I live in Maine and Florida but am willing to travel, or can it be purchased online? ive been searching but with no luck but i have purchased them in the past, many years ago, but cant find them available anywheres now! any ideas?

Answer
I have not seen such an adapter.  They do make adapters to make larger speaker holes smaller, but not to make small speaker holes larger.  I would just drill holes in the spots where the 6x9's would bolt in.  Then, if you really wanted to make some work, you could cut the hole a little larger to not cover the speaker.  Hope this helps, Scott