the other question is, in order to run the lines to that
split unit to the outside condensor/fan, we need to drill
openings in that load bearing wall. so if you go in between
the studs, it should be fine - right ? - how would a
reputable contractor seal up these holes after they've
run the lines ?


The unit will come with a sleeve that goes through the wall. The one I
installed required a 2" hole

--
Dennis