i have a 4" brickledge and had z flashing made to extend from the sheathing to then overlap the top of icf block. I am not installing brick, but rather xps foam. my question is what is the correct way to overlap the flashing at both an exterior and an interior corner?. looking at it i can see there are several options. i thought it would be best to find out what the best way is before i start with the tinsnips. thanks.