garage band merge of midi tracks

Is it possible to merge two MIDI tracks into a single track, with the resulting track keeping all the notes from both tracks? I want a "merge" in the true sense of the word - a product that contains the contents of both tracks layered one upon the other.

To be clear, I am not asking how to merge or Join regions within a single track; I am not asking how to overwrite one to the other, which thereby eliminates the notes of one in the process.

My goal is to ultimately use the Score button to generate the musical notation for export that is the composite of the two MIDI tracks' notes in one piece of music.

Using GB 10.4.8.