Mercedes Inline 4 Flathead production year identification

[Mariiboops]

I picked up an engine block for practice fixing up engines from decades ago. I thought I picked up a 50s model but I'm getting conflicting imagery and evidence on Google about details. I've landed around 1948, but I'm curious if there's a more concrete way to identify the year. Engine is complete minus an oil fill tube. I need a production year for more accurate replacement parts, although it's mostly out of curiosity. I know there's a minor chance it might be 1930s even though I may have already ruled it out.

[daniel boeve]

This is a early engine from a Mercedes 180 gas (1954-56) .Was the same engine as the 170 Mercedes till 1954.I own such engines also .

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