I purchased a "bolt in" replacement from Quality Power... I gave them the serial number on the stock RB25DET alternator and the provided me with what they assured me would be a direct bolt-in 180A replacement...ehhhh, not so much. The plug did not work, ie the battery was not getting charged (posts on alternator had different current configuration than factory unit apparently), and the ears were in different locations than the stock unit. I called them and they insisted that it was the right alternator, but then told me I may have to fabricate a bracket, and they also told me how to bypass the factory plug and wire it so that it would charge... not exactly "bolt in". The ears were off ever so slightly...however it required me to have the factory bracket modified. I had to cut it and have it re-welded with an offset. You can see in the picture the top of the bracket that used to be a straight piece, and now is somewhat like a "p" due to the offset. Aside from that the alternator works...it did have a slight squeal from the bearing on start up that eventually quiets down when the car is warm...not the greatest experience overall. I did not test the actual amperage output, so I'm assuming it's as advertised. Ultimately, had they not advertised it as a direct bolt in replacement, it wouldn't have been such a frustrating experience as I would have known going in I had some modifications to make. But when you are told it's bolt in and it requires fabrication and re-wiring it's quite a letdown.