Honestly, the right way to do this is to drill right into that pretty chrome mandrel bent tubing, throw a plastic or rubber seat (might have to fabricate one) in there, and seal it off with some kinda heat-resistant sealent. Again, I'm not sure as to the specific layout of the '94 Corolla, but I'm guessing you've got some room under the hood. Pick a spot where there isn't too much crowding the sensor, espically things that might produce excess heat, and mark off a hole. Drilling right into the side of it will probably be the best angle to put the sensor in.