C5 suspension components look to me, to be robust enough.
The thing to watch with C5 spindles is the location of the steering arm. There ARE kits to fix this, but the stock location of the outer tie-rod end sphere requires a very high placement of the steering rack to make the bump-steer work. This either puts your engine up higher, or requires you to move it backward.
I used Solidworks to design the suspension and frame for my Nova project. It helped a ton!
