If this were my coach I would do the following:

1) Pull off the Smog/air pump
2) Replace the intake Manifold with a Dual Plane Edelbrock Aluminum designed with no EGR valve.
3) New Large flow Cast Iron Exhaust Manifold, with new down pipes to the mufflers.
4) remove all of the vacuum lines except the canister and the valve assy. to keep the gas tank evacuated.
5) install the new FiTech throttle body injection system and O2 sensor. It is completely self learning

My 2 cents...Mark

I just posted on this old topic, because there was some frame work posted in the topic. Go back to the middle of page one for a comparison on the frame work.