headers or manifold?

Exhaust manifolds will last dang near forever, but also , there very restrictive. If you choose this route, take a good look at Comp Cams and there cams designed for exhaust manifolds. They have alot of exhaust duration to help balance everything. They work very well.

Headers free up much power. On a dead bone stock engine, the raise can be an easy 25 hp and a butt dyno won't miss it ever....unless your numb.

The draw back of headers is the instalation time and extreme effort not to mention that you will....and Ohhh you will....bang and dent and flatten out 3 tubes on the drivers side when you hit a bump, pot hole or debrise in the road.

3 tubes of the header run under thefront end steering linkages.
Of course, to avoid the 3 tube header crunch, there the expensive set's of headers, tti's and a slightly cheaper, Doug's. Member has them here; http://www.forabodiesonly.com/mopar/showthread.php?t=90717