Those are some nice drawings! Looks like I was on the same page as you. I went out this afternoon and made some marks and found something I liked. So I started cutting those ends and I like how it turned out. And now Its pretty close to what you had.
I am actually not using the factory hitch bolts. I thought about it, but I am going to try and use all 6 factory mounting holes, plus 2 more. I cut some
1/2" plate frame brackets to tie it in. Then going to add 1 grade 8 through bolt on the frame where the factory put in the elongated hole each side.
Then somehow make and weld a bracket to the bumper to use the other 2 cross member mounts.
Here are a few more pics of my progress, with more to come over the weekend.