Two things will support massive revving like that: Air and Fuel.

There is one hell of a leak around the throttle body somewhere, plain and simple. A mis-wired TPS will make it run rich, but not make it go into run-away. The wrong ECU will make it run rich, but not make it go into run-away.

Was the TB modified in ANY way? If the throttle plate was removed for any reason, chances are it was put in backwards, or off-center. It's got a beveled edge so the plate can close without catching the bore of the TB. Otherwise, the IAC valve could be stuck wide open. Throttle body gasket? Broken vacuum port? Hole in the intake manifold, leaky IM to head gasket. All those things will cause your problem, so check carefully.