Identifiying the Buick,Oldsmobile,Pontiac 54975 Bellhousing

The "975" is an aluminum B.O.P Bellhousing.
Warning : I have found at least 3 different versions of this bell.
These Pictures are of one version that is identical(except for the part #) to the 9795581 and 977822 clutch housings.

Photos of the other two will be coming soon.

Top view
In this picture you can see the two starter housing (ears),
which allows it to fit Buick,Pontiac and Oldsmobile engines
.

Part#
Part number is cast into the drivers side starter "ear".

Top
The "V" at the top of the casting is another B.O.P. identifier.

Fork side

Bottom
This bell takes the same type of,
one piece sheet metal clutch inspection cover as the "581" and "882" clutch covers,
that is held in place by three 1/4"-20 bolts.

Side view

Engine side
Here you can see the two starter "ears" and the engine mounting flange,
with six clearance holes for bolts and two dowel holes.

Inside view
This picture reveals the fork mounting stud location and beefy reinforcements around all mounting holes.

Disclaimer:

Factory correct applications are your responsibility. GM made part and part # changes with no rhyme but a reason (no production interruptions at any cost).
Application charts are for replacement parts that were available at the time of parts book printing.
My observations come from the parts I have in my collection or other reliable sources your parts may differ.
If Factory correctness is your goal, do more research, join car clubs,
forums and buy an assembly manual if one is available for your Project Car (you wont be sorry).
This is a fun and interesting part of the hobby!