I see that the 92-93 Prelude uses a TCU numbered 28100-P15-A21 or A41 depending on which motor is in the car. The 94-95 uses a TCU numbered 28100-P15-A22 or A42. I have been trying to find out what is the difference between these TCU's with no success. Is there any difference or is it just a model year numbering change?