I have an issue finding the correct starter

[mookiex4]

I have a 65 GMC truck that I had my local high school install a Late 60's 283 that was rebuilt to a 327. I have tried one of the starters the the two bolt install vertically or straight up into the rear of the block. It will not engage the flywheel. I have bolt holes for the bell housing where the type of starter can mount, which is the way I am used to seeing a starter mount with 3 bolts.

Can anyone give me guidance? I have noticed that when looking for a starter they are designated by transmission type, such as 3 speed and 4 speed manuals, poerglide and automatic transmissions. Mine is the 4 speed with the granny gear. Is this considered a 3 or 4 speed. Who ever uses the granny gear unless you are planning to pull a house off the foundations. HA!HA!

Really guys, starters are not cheap to keep buying and returning. Thanks in advance.

Mark