What am I missing here, the high load/short condition is only present with the key on? All these comments are about the alternator or alternator output wire possibly being shorted? All of that has un-switched access to the battery. Start by disconnecting the engine harness from the bulkhead connector, see if the condition remains with the key on. If not, the issue is in the engine compartment, ignition 1 circuit (blue/tracer). If the condition remains with the engine harness disconnected, the problem is on the dash side, again, blue/trace wire in the bulkhead connector running to the ignition switch Molex connector, or on up to the ignition switch.
If the problem started with work performed to the steering column, likely the blue/trace ign. 1 wire is pinched under the column mounting bracket, or otherwise shorted to the column within the column. Another test, disconnect the ignition switch Molex, jump the red and blue/trace pins on the dash harness side of the Molex, if the high discharge/short indication does not register, the problem is for sure in the column, wire pinched, or short at the switch. Or as marks ebody suggested, if you have access to another ign switch, plug it into the dash harness without mounting it and see if the problem goes away.