2bbl conversion -- worth it?

Actually, the 71-77 camshaft was the most "radical" installed in the 225. There are several aftermarket camshafts available. Check here and over at SlantSix.org.

Good luck finding an intake that will allow the throttle shaft to be installed parallel to the crankshaft. Most I have seen are perpendicular.

As for kickdown linkages, consider either a Lokar or Buchillon Performance kickdown cable.