If you are restoring an older car that requires you cutting off one or both quarter panels be VERY careful when it comes to cutting the lower rear section of the quarter panel. On a couple different jobs I found live shot gun shell laying down in the bottom of the pocket where the trunk floor extension/lower rear quarter panel meet. Most of the older cars were pretty much open in that area where you could reach down from inside the trunk and make sure that area is clean before you start cutting. But some cars don't have enough room to reach in that area but enough room for a shot gun shell or a road flare to roll into.
Just one more thing to be careful about when doing bodywork.