I've never seen photos of badly damaged P-51s having returned back to base (I'm sure some exist), where as such photos of the P-47 are easy to come by. There certainly appeared to be something more robust about the Thunderbolt's airframe and engine.
Google P-51 battle damage. There are quite a few pictures there. Remember, saying that the fragility of the P-51 is overstated, is not the same as saying that Thunderbolts weren’t tough as nails. They undoubtedly, were.
Oldplayer