OK, this seemed like it would be a easy job, replace the alternator on my 440. Picked up a replacement last night from Napa, started install after lunch today, figure it would be an hour job, tops. Everything went on fine until I attempted to install the tension bracket. The 5/16 X 18 bolt that was in the alternator that I took off was a smidge too small. I tried a different bolt (same size), same issue. I brought the alternator back to Napa thinking the holes may have been stripped and swapped it out for a different one. New alternator, same problem. Tried a metric bolt that was a teeny bit bigger, still not big enough to tighten properly. Next size bigger bolt in both standard and metric are too big. Before I helicoil, is there a special bolt that I should be using? Nothing came with the alternator.