I have a cedar home with a lot of nooks and crannys outside and bugs inside.I pulled the Panal off the wall inside and found 1×6 cedar boards on the walls (not lap siding just plain boards(but) there a 1/16 to 3/8 cracks between each board. calking gun tip is to large and don’t want to get filler all over the boards. Any Ideas ——????? Help, thanks Paul