Hi
I have two 300hp marine diesel hammerheads in my boat
They must have been 6.2 originally
bored to 6.5
I bought a new starter from ebay usa
to fit one off my engines
The bolts were the normal vertical ones that would not fit the block!
We ended up changing the old front end off starter with new motor parts fitted to use it
Have i bought the wrong part or is there different ones for these blocks ? Sorry no truck info available

 

Don't know much about the marine versions of the 6.5 but vertical bolt holes into the block are for automatic transmissions and horizontal bolted ones are for manual transmissions.

Hope this helps.