Thank you very much for both your answers!
Could you please clarify the identified objects: the Gun Panel Catch is the part on the 4th photo? (with red text) and which one is from the Control Column Mount?

*And is it in any way possible to identify a Spitfire (serial number) merely by these partnumbers/inspector stamps …?

We are planning to dig up some more parts in the next weeks. I will post photo’s when we find anything else which differs from the parts already found.
Thanx again for your help!