The book 'Airframe Construction and Repair' by John T Henshaw, Pitman 1943, has information on repairing tubes:
Also 'quick' release fasteners for access panels were common, these are from my own technical training notes from the early 1970s, but on the whole in use by WW2:
The Amal, for instance, was used on the Hawker Typhoon and other Hawker aircraft, the Fairey was used on the Spitfire, but also they were used on interwar aircraft.
Good very basic reference but first option always is what is specified in the manufacturers manuals - in this case AP 1564B Vol II Part 3, written by the factory to an AM specification. In the case of the Hurricane the tubing used was not a weldable alloy so only scab patches could be used. If you looked at MiFlyer's earlier post it is unlikely that a scab patch could be used on any of the cluster joints so that only leaves replacement.
If major load carrying components of the fuselage assembly are damaged and the assembly needs to go in a jig, it might be more economical to scrap the aircraft but without a detailed hidden damage inspection, your assessment is a very wild guess to say the least. To say a P-40 "would have" faired better is even a wilder guess!
And "scrapped" Spitfires were sent to the nearest factory to be upgraded to the latest model and given a new serial number.
If the wings were perfect they would just get a new serial and new paint job. If not the same as the fuselage - upgrade and reserial.
One of the reasons why no-one knows how many Spitfires were produced.