Thanks, that sounds like excellent advice. I will replace the EGR/intake manifold gasket with steel plate, pull the vacuum lines, plug the sensors and put an end to exhaust emissions being routed back into the engine. Also minimalizing linkage and discarding what's left of the vacuum rats nest on top of the valve cover. Expecting better performance, less liklihood of carbon fouling. And yeah my '79 fully operative parts car has NO butterfly valve, so will pull the one on the '83 when installing the plate.

I want to keep the '83 manifolds just to have the oil separator. Even at 250k miles on the '83 compared with 179k on the '79, the '83 car uses noticably less oil. Difference of several hundred miles per quart - like about 2000 compared with 1500 miles per quart.