Engine Block Serial Number?

[dtcerrato]

Need to supply parts houses with serial #s on engine block to order rebuild kit.
Can't find a number on my inline dd 671 that looks useable!
Please reference photo attached and chime in.
The photo is where Detroit literature says it would be on a coach engine (blower side of block, upper right corner)
The only other 3s on the block are on the cast surface under the blower (5111434)
There are no other #s on the block
Do these #s make any sense to anyone?
Notes:
1) When I purchased a replacement starter from Luke recently, he & his mechanic were stumped about interferences in the bell housing to get the starter to work.
They mentioned it may be an industrial type bell housing.
2) The engine in our 53 - 4104 is a 1969 block & may not be originally from a bus.
Any thoughts?

[luvrbus]

Gray Marine port side

[dtcerrato]

Thanks Cliff, I needed that...

[luvrbus]

You don't need the serial number anyways,when you give them the serial number they send you the parts for the original engine specs and it sucks