I'm not sure about the 07, but I just replaced the 4 door speakers in my 16 Elantra and it was fairly easy. Mine is technically a 6 speaker setup too, but I didn't change the little tweeters in the front doors, they were okay enough. I took the door panels off, pretty easy, hollowed out the stock speakers to use them as adapters for my new 6.5" speakers, bolted them up, wired them up, put the panels back on. I was done with all 4 doors in about an hour, and I took my time too. Not bad at all. Yours should be similar. I used JVC speakers that I got new on eBay for $25 for all 4. They sound a heck of alot better to me. No distortion, clean sound. Bass might be a little less with the new speakers, but that's a plus to me. I hate bass, and all I listen to is classical anyway. They aren't broke in yet either, so might sound even better after awhile.