Anyone have advice for Cusco brace install?

I attempted to again install the Cusco Power Brace Rear Member Side (687 492 rs). This install is frustrating. First problem is the rear lateral control arm doesn’t play nice when unbolted from the frame and won’t easily line back up to accept the new bolt. Bigger PITA is the other attachment point. They direct you to use a hole in a frame piece that is a bit big so they provide a bracket with a nut welded to it (lower left in linked pic) to slip in from a side slot in the same frame piece but the bracket doesn’t sit still and is loose in the area behind the frame hole. With only two hands it’s hard to lift the brace and try to find that nut and engage without it getting squirrelly.

Anyone install this part and have a tip?

https://d1vv73x37cbx43.cloudfront.net/media/catalog/product/cache/4/image/9d3082b4bec2d774d16a712307ac9d2a/8/8/88279_4_b9ec6e20-681d-4411-bd99-630476390dca.jpg