What are the advantages and disadvantages in using the 1/2" spacers used between the K member and frame? Also is it worthwhile to move the steering gearbox closer to the frame to give a little more room between the steering shaft and the head/valve cover? I found it is a little close in the rear corner where the steering shaft exits the firewall. The steering outer tube has been cut back to clear the head already. I found by putting in the 1/2" spacers it moves the head from above to below the steering shaft. Either way it's close. The engine is placed in the dimensions given by tti.

Well they were used so the Hemi would fit in the A-Body's, I don't know of any advantages or disadvantages, only the reason they were used. There were other changes like the bump-stops on the control arms, hammering the inner fenderwells, and master cylinder offset block.