Question: Which original stories were the archival shots that Clara was retconned into taken from? The only one I know for sure is Pertwee Driving Bessie in "The Five Doctors".
First Doctor: Not sure.
Second Doctor: The Five Doctors.
Fourth Doctor: The Invasion of Time
Fifth Doctor: I'm not sure but I want to say either Four to Doomsday
or Resurrection of the Daleks.
Seventh Doctor: Dragonfire.
I'm pretty sure that was Arc of Infinity for Davison. Didn't he enter the matrix while facing off against Omega?