There are a number of recorded and well documented (including photos) instances where RAF Allison engine Mustangs conducting low level tactical reconnaissance or offensive operations against targets in occupied Europe received extensive damage to their wings, fuselage and other parts of the airframe from enemy flak or fighters (or wireless antennas, telegraph poles, and even a church steeple) and made it safely back to base at distances greater than 100 nautical miles.
Two examples.
One. Mustang IA of No.268 Squadron RAF, flown by Squadron Leader Pallot DFC, on a Tac/R during Operation STARKEY on 2 September 1943, pair of Mustangs 'bounced' by four+ FW-190s, 20mm cannon hit to port ammunition tank, extensive damage to ammunition tank and armament bay, armament bay doors, shrapnel/splinters to other parts of wing, fuselage and underslung radiator. Made it back safely from location where 'bounced' near Hesdin, France, to RAF Odiham, 155.96 miles direct, flew slightly longer path to exit French coast away from known flak hot spots and to enter UK coast at designated low level entry point. Aircraft sent away for major repairs, returned to service 2 months later.
Two. Mustang IA of No.268 Squadron RAF, flown by Flying Officer Mitchell, on a low level 'Rhubarb' against targets near Abbeville on 25 September 1943. Hit by 20mm flak near Poix Airfield whilst attacking steam engine on rail line near airfield. 20mm flak exploded in wing armament bay causing extensive damage to ammunition tank, blowing armament bay doors partially off wing upper surface and damage to lower wing surface, under carriage gear door, shrapnel/splinters to other parts of wing, fuselage and radiator housing. Made it back safely to RAF ALG Funtington from Poix, distance over 146 miles return to base.. Safely landed. Sent away for major repairs, returned to service three months later.
Plenty more similar instances, including one pilot who got a very close 88mm flak burst into wing root area, did significant damage to wing, adjacent fuselage, peppered the pilot with shrapnel, made it safely back to base for a shakey landing, aircraft condemned/scrapped after landing. In his case he was a bit 'luckier' as it was after D-Day and Squadron at that time was based at an ALG in Normandy so only had to fly about 50-60 miles back to the ALG and not fly across the Channel.