Thanks for the info. About seams, my roofing carpenter expresses concern about the seam that would be created by adding the fake gutter box onto the edge of the rafters. His concern, if I understand him correctly, is that the seam would need to be flashed and sealed, and then he would worry about nailing the shingles down and piercing the metal flashing, thus opening up the possibility/probability of future leaks. What puzzles me is that there are seams all over the slope of the roof, because the plywood underlayment(tech-shield) is not butted too tightly, to allow for expansion and contraction of the plywood from season to season. The seams of the plywood are not flashed, nor are they treated with any special waterproofing, other than 30# roofing felt. So, why would it be much different in the case of the seam at the "drip edge", where I would like to install the fake gutter box? Second question, should all the seams between the plywood be covered with the water shield?