Why?

can you still run power steering with the hemi and headers installed?

I haven't personally, though I believe there are a few different solutions at the moment. I guess it sounds like the Borgeson box is now out, I think that was still in development when I did the swap a few years back. If you go the more expensive route and pick up an Alter-K I think you can do a power rack with modified Chrysler or regular GM pump. A few people have done rack swaps on stock K members as well that might be an option, but I think typically the steering geometry is less than ideal. Power brakes aren't as much of a challenge, though it can get pretty tight in there. I ended up removing my booster to give some extra space and because I think it was on the way out anyway.