Well, don't know if my approach to cooling my 350 was an overkill--but I don't have an overheating problem. And that was my goal. I grafted 1/4x2x7 tubing into my "frame" horns and installed a steering gear out of an WJ Grand Cherokee. This box sets on top of the frame and gives about 3" more clearance between the "box" and the pass side frame; additionally, I notched the pass side frame (my added tubing) ~1", so that a Howe 2-core, 19x26 aluminum radiator would fit (part #342A). I also extended the frame rails and built a new front cross member. The new steering box required extending my drag link ~5", and marying the lower end of a WJ steering shaft to my XJ's upper shaft (different shaft u-joints).
Moving the "box" over also solved clearance problems between the exhaust manifold and the stock Chevy fan.
Manifold problems ocurred because my local SMOG ref required I use late model truck manifolds, which are significantly wider than car applications.
My stock XJ pitman arm bolted right up to the WJ steering box. I did have to modify my driv'rs-side sway bar drop bracket to clear the pitman arm when steering is hard over to starboard--even now, it just barely touches the sway bar. Also, the power steering fittings from the Chevy are the same as the WJ box--thank god. I'm also using the stock HD fan clutch, and a home fabbed shroud. Well, I could go on for pages on this swap--but, the short of it is, technically, my new radiator barely meets the basic requirements of cooling a stock 350.
According to my research, the cooling area of a radiator should be 50sq inches greater than the cubic inch size of the engine; however, My engine temp stays arround 195* off-roading and city driving, and ~195-200* at highway speeds (fully loaded with camp gear and weeks worth of provisions); a long, hard pull in 5th(yeah, I love the power!) while passing some one uphill has resulted in a max of ~210*. So, I'm happy. But as they say, you get what you reap.
