my 67 d100 needs a starter all I see on line have two mounting bolts mine has three what gives

That's interesting…not many 3-bolt starters on Slant-6s! What kind of transmission does your truck have? Anyway, the 3-bolt starter you need is here (can't see the 3rd hole behind the nose cone, so here's a pic from another angle:)

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Too many people who were born on third base actually believe they've hit a triple.

I am so glad you answered. You seem to be very knowledgeable and I am a newbie. Trans is a three speed on column. I was wanting a new mini starter. Is something like that available? Again thanks a lot

A 3-bolt mini starter would be a very costly item, because it requires significant custom-machined parts. You will not notice any benefit from the lighter weight of a mini starter on a vehicle such as yours.

Very strange that you have a 3-on-the-tree transmission and a 3-bolt starter. I don't mean to doubt you, but have you actually pulled and examined your starter and you're sure it's a 3-bolt item?

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Yes. I bought a starter on line before I took my old one off because it is my daily driver. Needless to say it didn’t fit. I was told all these old mopar starters were the same Leave it to me to get a mongrel !

Best go ahead and get the one I linked, bolt it on, and turn your time/attention/money elsewhere, unless you're into spending multiple hundreds of dollars for no real gain.

Other good places to spend time/effort/money: Tune-up parts and technique suggestions in this post, and also see here.

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Too many people who were born on third base actually believe they've hit a triple.

I am ordering the starter tonite. Funny thing, on amazon they ask to verify year, engine, make etc. they claim both two hole and three hole starters fit my truck. is it that strange of a combo? If its that rare I will sell it to you for about 100 grand. Thanks so much for the help and the link.

I've seen a few 63-64 Dodge trucks with the low mount starter 11" HD clutch and the 3 bolt starter... a 2 bolt starter will bolt up...BUT...
the 3 hole starter is a different beast than the standard 10 tooth starter everything else takes, as it uses a 9 tooth gear that will
match up to the 143 tooth flywheel....

I have experimented with installing the 11 tooth gear from a 1991 Dodge Caravan 6 cylinder mini-starter on a typical 5.2L mini-starter
and that combination will mesh and operate properly on the mid-70's to 1987 11" clutch bellhousings... I unfortunately do not have an
early-mid 60's bellhousing any longer to mock this up and test. It is not exactly economical either to buy 2 starters to build 1 hybrid...
(I got lucky and got the caravan starter for cheap in a parts sale and had a spare junkyard 90's V-8 mini starter laying around to experiment on).