The top one (actually two) is from the bottom of a TSIO0550 oil cooler where it feeds the turbo’s (for cooling) - at least that’s what was on my engine and seems to reflect the diagram in the TCM manual. The bottom one is functionally the same thing but is a single fitting that I got from a local hydraulic fitting supplier.
Also, some time ago, I replaced a 90 degree TCM fitting on the fuel pump with a 45 degree steel one. Now, I don’t recall if the original was brass? and/or don’t know if that was a mistake for some reason. I don’t recall anything in 43.14 regarding brass vs steel fittings in aluminum housings – but’s there’s plenty of stuff in there that I may have missed/forgotten.
Rick Titsworth