jhud202 wrote:
When you are in LR, activate the crop module and go into the aspect ration section and choose custom. In that module, enter the size you want the finished product (L & W-says aspect ratio, but don't worry about that) and hit the enter key. That will bring a crop box for those dimensions onto the photograph and you can size it via the handles to wherever the crop fits your vision. The finished, exported photo will be the size you need regardless of the "aspect ratio".
The whole question was not how to crop (the OP knows how to do that), it was how to make a stitched pano fit into a predetermined size (aspect ratio in his words).
From what he has to work with, he just simply can not do what he wants without cropping off portions of his image.