Zfreak, excellent job on your finds! From a true enthusiasts to another, this information is gold! I see you are quiet methodical when it comes to putting this "misinformation" to bed. I'm currently under going the same endeavor with probably the same amount of thought and energy as you. With that being said, I currently have a h22a4 and a f20b. The h22a4 is going to end up being torn down and rebuilt (possibly boost). Should you end up finding yourself pondering about differences, drop me a line. I'd gladly dissect the h22a4 to help you out. On a side note, sometime in the near future I will doing a "End all OBD1 f20b swap". If you don't mind I'd love to use some of the information and pictures you have provided. Again thanks for the great information! I will be turned in and watching.