Sorry, I forgot to measure that trim piece for you.
Measure up from the bottom 3" for the first cut. That should be right were the piece starts to angle. Refer to the picture were I marked the cut lines. As far as the width at the top. I'd measure how much room you have between the two lower pads. I have 4" there. My trim piece is less that 4" though and doesn't fit the best. I'd cut the trim piece so you have just less than your pad distance. The piece would fit better this way. Hope that helps. Sorry it took so long. You probably already have that piece cut.
