Ordered a new grid on line and proceeded to cut out all the fabric for an attic window. After everything was cut out I find that the grid measured 5 7/8" instead of 6 1/4". Now I am off on everything. I want to try and fit it all in but cannot figure out how to cut to size the triangles for the corner. They currently measure 2 7/8 while the main picture and and the light and dark measure 6". What size do I cut the triangles to match the 6" fabric. I am just sick over this but can't stop now because I have already invested too much time and money. I am desperate for any help at all on how to complete this quilt.