I got you re. the use of the 73-up stuff. No reason not to use it. Here's a little clarification with regard to the sway bar. Not only does the sway bar route differently; it is a different bar altogether...much shorter since it routes through the k instead of in front of it. This also means that the LCAs have to change to 73-up because of where the tabs for the end links are located. The pre-73 bar won't work because the 73-up calipers mount in FRONT of the discs instead of on the back side like the pre-73. Steering would cause the caliper assembly to interfere with the old style sway bar. All of this gets back to your original point...use the 73-up if you've got all the pieces.
After I started this thread, I went back and consulted my copy of "Performance Handling for Classic Mopars" by Tom Condran and confirmed all of the above. Should have started there in the first place...a great reference resource. Thanks, Tom if you're still out there.
