Alignment Issue

[rustiny]

Hello! I am attempting to put my 29 Roadster back together finally after two years of work. I don't like how the bumper lines up with the rear quarters on the back. I am trying to save what once was a disaster so I do have reproduction sub rails, rear wheel wells, and the triangular pieces in the rear. The rest is the original steel. The photos that I have before I tore it apart don't appear to have this big of a gap. I think it has something to do with the repro triangular pieces being slightly to big and rocking on the sub rails. They do not look exactly the same as the originals and my supplier told me that but, they do fit. Is this just a case of a 80+ year old car or something that I'm not seeing. Any thoughts or ideas would be greatly appreciated! Thanks!