Block identity

[rally 1]

This engine is in a 29 coupe that I just recommissioned, after sitting for eight years.
The block doesn’t have any ID number on the engine pad, and has this unusual oil drain tube.
Also, has some type of inspection panel, where a fuel um might reside.
It does have a cast in diamond by the timing cover.
I’m thinking that this was a warranty replacement?

Any thoughts?

Thanks
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