If the starter has two long bolts it's 168 tooth. If one long and one short bolt, it's 153 tooth. This has been my experience anyway. I have used both and have noticed no difference in cranking power. But one would think the larger one would be better. If you need serious cranking power grab a 6.2 diesel starter, throw away the center support, nose cone and drive. Have the small end of the shaft turned down to the smaller size of a gasoline starter shaft. Install the standard drive and a cast steel nosecone (I suppose an aluminum one would work also). It will then fit your application and spin it like hell. I use this combination on a 604 inch alcohol engine. Works beautifuly.
I have no idea if it will clear your hedders. I haven't had amazing luck with the mini starters. They spin so damn slow!
Note: not responsibe for incorrect answers, sorry I'm getting old.
[Edited by Moffitt on 03-07-2001 at 01:16 AM]