re: ATTN: contractors/engineers of the OB

That is easier to do, talk with the super, tell him to frame up a header and then drywall it in so it can't be seen, slip him some money. Then after the wall is completed, you just need a little drywall work, paint and a little wood trim...

That should be fairly straightforward and I like the look of that a lot

eta: you could do that yourself with minimal skills