If I wanted to use charm packs (5" squares cut diagonally) instead of turnovers (6" squares cut diagonally) what size would you make the rectangle that goes with the triangles on Jenny's tutorial? With the 6" turnovers the rectangles are 3 x 8. Would you cut the rectangle 2.5 x 7? I have a lot of charm packs and thought I could make some stack and whack lap quilts from the charm packs instead of the turnovers. Thank you for your advice!