Hi Dominik, looks like you're in deep! A couple of options on relocating the pivot points for your upright. There are several different brands of ball joint available for race cars that are adjustable in length to shift your pivot points to desired height. If you need more info on them let me know, they're quite inexpensive. Once you have established dimensions that work, whether it be pivot points or a-arm length's, you can use your adjustable set up dimensions to make something more permanent if you wish. The adjustable set up can often be used as a jig to fab the permanent set up. Uprights (spindles) can also be custom made by outfits like
www.stockcarproducts.com. Keep reading about it but don't drive yourself crazy! I am VERY interested in your project as I'm about ready to commit to rear outer pivot point locations on original spec rear suspension. Keep posting pics and talking about it. I'll get a few of my rear suspension in my gallery shortly.