I will swear by the small N-D alts.  mine has 800 hours in my O-320, spinning at 8000+ at cruise.  I was lazy and left the internal reg in it.  i recently put a rebuilt one in after finding a bit of bearing play, $106.  i did have to drill the mount bolt out to 5/16ths(?) to match Vans generic alt. mount. i have a blast tube on it too.
Kevin Lane  Portland, OR
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