Sub frame woes

And the reason to replacing the front clip was due to excessive frame rail rot on my original car. Most ppl would of used my car as a parts car but it’s my highschool car and the sentimental value far exceeds common sense. Thus the installation of the donor clip.
Okay. I was worried that it had sustained damage and that that could be your issue. Like what has already been offered, you can kinda throw all of those measurements out the window and use the sheetmetal for the final answer.