Im thinking of replacing both rear quartershowhard of a job is this?

 

There are a lot of guys that have done that here. Do a search to answer most of your questions. It's not that hard for some, but plan of these things. Have a decent sized work area, the proper tools, patients, and the ability check your work 10 times before you start spot welding. That means all the dimensions must be correct. The PO of my car did not do that. My rear valance was more than 2" too wide because they didn't spread her cheeks wide enough. It's all the little details that can mess things up in the end. Everything must be set right in order for all the other parts to fall into place and all the body lines to line up. Don't let this scare you, if you can take your time and check all the dimensions that are available on this site, you can do it with pride and know that you were the one who rebuild your mustang when it's all said and done. Good luck.
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