On the alternators, you may have to remove a little material on the two lower screw bosses in the unit so that it clears the mount. Too many variances for Jerry to compensate for especially if you get a chinese unit like I did from RockAuto. If you get a legit Nippondenso oe unit it will probably be a non issue, but still check just to make sure. I really like how his looks and that replacement service units are readily available. Well worth the money and less blingy than the others out there. Anybody read a Hot Rod magazine from a few months ago showing a 66-7 b-body with a hemi that Rad Rides by Troy did? They used a Billet Specialties unit that had a part fail on a photo shoot road trip and could only source it from BS. Not cool. My neighbor has run BS stuff in the past on his rods and said thats a known failure issue with the idlers and can only be had through the company. Not helpful or fun on sunday if you are cruising where there are no BS distributors around.