how to write a single note that covers two sounds

[Edmundo Carmona Antoranz]

Hi!

Suppose you were transcribing Bach's flute partita BWV 1013 from
manuscript. On the Bourree, on bar 48 there's a note that was
corrected on the manuscript but, if you ask me, it's kind of difficult
to see what Bach's final intent was. Was it a F that got corrected to
G or viceversa? So.... if I wanted to keep that same problem on a
lilypond transcription so that the reader of the part can figure it
out by themselves, how can I do it? I've already found the "\tweak
-font-size" option and I can get a bigger note with it but it's
"centered" around one sound so if I enlarge an F so that it covers the
G, then it would also end up covering the E (plus it still looks as an
F because of the note being centered on that sound).... same problem
if I write G (to cover the F it would also cover an A.... ) So....
having a "bigger note" already in place, I'd like to displace it
vertically to be centered right in the middle between F and G. How can
I do it?

Thanks!

PS Oh... and by the way, this is for https://github.com/eantoranz/bwv