Hi ehall928, Your stamp is a #11 and, as stampcrow indicated, it was printed from plate 4.
I downloaded your large image and straightened it in an image editor. I then compressed it to 10 percent of its original height to enhance the curves in the side frame lines. Using this technique, I was able to compare your stamp to the Carroll Chase Smithsonian plating prints for plate 4, and the plate 4 images on stampplating.com and plate your stamp to position 76R4.
Here is the compressed image of your stamp overlaid on the compressed 76R4 image from stampplating.com to show the matching right frame line. In addition to the curves matching, the right frame line is thinner in two places; near the middle and near the top:
