I personally dislike flashing because there's more risk of compromising the gradation of the low values. Split printing on a high-quality VC would make this a fairly easy task provided the high values
of Mt Conness aren't blown clear onto the shoulder of the film and still retain some gradation. I'd simply make a relatively precise cutout on a burn-in card and give that specific area some green or
yellow light exp. (Actually, I'd personally use a registration punch and special mask to do the burn
exactly, but most people don't own that kind of gear). Good timing with that shot, however!