Red, black, silver, some sort of combo, it just doesn't matter. This is your job and it should suit your taste. I think what you have done looks great. You choose the valve covers.
Here is one we did.
As for the yoke, if it works, use it. I don't think I would trust that yoke with a complete 930 engine (too heavy) There is a company that makes a Porsche adapter for this type of yoke. We bought one and it works well.
