I presume I've been on here talking about (8) windows that were installed just about two years ago. I muddled through putting in the extension jambs last fall. I've cut the stools and tacked them in (prob going to rent a 15ga finish nailer to finalize them). Its an old house. Plaster removed and replaced with drywall. installers didn't level the walls. Most of the legs of trim (~60") aren't going to complain about the walls, But there is one in particular that is about 1/2" in (the wall sinks to the outside) starting at about 35 inches up from the stool. Its an even slope (about 1/4" at the 48" mark or so. I've puzzled quite a bit. the drywall is full-weight 5/8" and the trim board is 5/4 select pine ripped down to 1" (a true 4/4). They're 4 7/8" wide. The board will bend if I hold it in place. My concern is how to make it hold at least for a decade or so. The board will be painted so I thought why not screw it in? Seems like Finish nails might not hold with that kind of "pull" on them. Luckily I established there is a stud just inside the outer edge of the board so I got something to bite. What say you all? I've got some Hillman Power Pro 3.5 and 2.5" or some SPAX 3" #10x. I think its the Hillmans I really like for driving, they run like butter. Is screwing the answer? (for this issue !!:nono I didn't like the idea of "furring" that gap -- it just seemed like the trim board would be intruding on the room, it would stick so far out from the wall (I think the wall falls further "in" as you move away from the jamb at that height). Even toyed with the idea of disassembling that ext. jamb, and replacing it with one that extends out to the plumb line at the stool and also putting a bit of bevel on it so the board's outer edge would find the wall surface. On the other hand I could do the same idea with a "furring" (wedge) yes? As a diy'er there are two things I find myself saying quite often: after coming up with solution I'll say ". . . and then I'll caulk the s$#t out of it" the other is a a ditty sung to the tune of the Hanukah song "Draedl, Draedl" (whatever that title is): "Dremel, Dremel, Dremel I'll fix it right now. Dremel, Dremel, Dremel and I won't have a cow." thanks!