Doug's are the highest sitting long tube headers you can get for a small block A body. They sit 3/8" to 1/2" higher than the similar TTI's, and both the Doug's and the TTI's stay above the steering link.
They still hang down lower than the exhaust does for stock manifolds or the shorty headers they make now, but you can't do better than the Doug's for a long tube. My Duster uses the poly "button" style LCA bump stops, and I have the ride height set so that I only have about 1" of clearance to the bumps at the moment. I still have almost 4" to the header flanges. When I get the new rims and tires on it I'll probably lower it another 1/2" (ground clearance, not LCA clearance).
You'd pretty much have bottom the LCA's out against the frame to bottom out a set of Doug's headers. Maybe if you like crashing speed bumps at 30mph...
