115-490-05-19 is for 240D W115 chassis up to 200000.
115-490-13-19 is for 240D W115 chassis 200001 onward.

1976 was the last year of production for the W115 240D. so you probably need the second version.

Hope this helps.

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78 W116 300SD 'Desert Rose' new as of 01/26/2014
79 W116 300SD 'Stormcloud' RIP 04/11/2022

Thanks for this. I now have both pipes in my possession and neither of them fit. Picture comparison of the 2nd version (on the left of the shorter pipe) which I ordered after my initial post below.

The plot thickens...

Attached Thumbnails

   

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Why I will never do business with "DieselKraut" again

http://www.peachparts.com/shopforum/mercedes-benz-used-parts-sale-wanted/378935-why-i-will-never-do-business-dieselkraut-again.html

Are either of these P/Ns indicated as correct for RH drive vehicles?
RHD exhaust manifolds/downpipes generally differ from LHD.