I have attached an image of the Draw-Tite Ultra Frame Trailer Hitch Receiver # 41947 referenced in your question with a few dimensions labeled.
The distance between mounting holes, from the left side mounting bracket to the right side mounting bracket is 30-1/2 inches. The distance between the mounting holes, center to center, is 3-1/2 inches for the closer of the two holes and 15-7/8 inches from the hole nearest the receiver to the rear bracket hole.
If you need any additional measurements,... view full answer...