Hello. Please see attached photos. The first photo is my house and a crude drawing of a porch i am putting in. It will be built out of cinder block and clad with limestone block and the surface areas will be bluestone. I know it is not good practice to have masonry against wood. I plan to cut out the cedar siding around the area where the porch will be and have read about putting galvanized metal flasing where the wood is. What do you think? How do i handle the threshold as to how far should the step down be to the porch? In the area marked "B", how would i finish the vertical joint where siding comes up to the new stone veneer? Leave a gap? And caulk? In the area marked "A", i have seen where a piece if copper is placed behind the siding where ut would meet the bluestone surface with a kerf cut in. I posted pics as well. Any pointers would be appreciated.