i don't think it would be worth it. i have put 6x9's in truck doors that were originally 5 1/4 openings. the main thing you need to worry about is the window regulator(the moving parts might hit the back of the speaker). the only way to fit that size in the door is to actually cut the sheet metal with a saw(i use a air tool). the opening should be the size that would accomodate a 6x9 speaker. you can use dynamat in the opening to make a surround for the speaker. also once you get the speaker in there, you have to worry about the door panel pressing on it or not clipping in all the way around.