What is the difference? Is it just a 170 versus a 190/225? That would be high deck or low deck though... I've read all of the articles, etc. What did I miss?

High starter is a starter above the oil pan, low is below the pan. I believe the low starter bellhousings were truck/van items.

The low starter was used in trucks and that is really the small block V8 starter position.
Mopar used a special adaptor plate or bellhousing in order to use Heavy Duty V8 transmissions behind the SL6. Seeing these are the V8 trannys, the starter is in the low V8 position.
DD

I don't know that I've ever seen one. Now I'm gonna start looking. All parts, etc are interchangeable, right? So, in order to put a low starter engine out of a truck in an A body I would have to use the truck transmission as well? Thanks.

Rob

The low hung starter usually comes on the HD manual tranny truck setup.
This is a larger cast iron bellhousing, mated to either a 3 or 4 spd in the 60's, or in later trucks can be a NP435. I just pulled one a while back for one of our board members. The bolt pattern is such that it eliminates the use of the 'stabilizer ear' that you have in your car now under the high mount starter.
You also have the adaptor plate that doc talks about, and AndyF is working on a version of it right now...

The trick of pulling the 'big' housing is to bring some wobblies.. and a breaker bar... You have to remove the tranny first, the clutch assembly next, then the flywheel, then you can unbolt all the bolts and the 3 hidden ones at the top of the bolt circle near the 'cylinder head' inside the housing.

-D.Idiot

I pulled on of those out of an '80 1/2 ton. It used a 11" clutch. The bellhousing wraps around the flywheel and the flywheel needs to be removed before the bellhousing can be removed. No adapter plate was needed. An A833. will not bolt on, but it does have holes for the 3 speed and NP435. The clutch linkage itself, appears to be the same as used on the F-bodies. It would be a very tight fit in an A-body.