Similar idea, but not quite the same part. The '73-up factory choke modulator adjusts power on the feed side of the choke heater, which has a constant ground. The black box that comes with the choke kit adjusts resistance (in accord with engine temperature) on the ground side of the choke heater, which has a constant feed with ignition on. You can fine-tune the behaviour of the aftermarket electric choke by choosing where to locate the ground modulator. I usually used the rear one of the two threaded holes facing the sky on the cylinder head, just inboard of the manifold mounting plane.