Roof Rack Bolts - M6x16?

Can anyone confirm our roof rack bolts are M6 x 16mm?

I searched online and everything on E46Fanatics and elsewhere says that’s the size, so I bought some; First at Home Depot, but they wouldn’t thread more than 1 turn before they started to bind, so I thought maybe they got mixed up in the bin and were the wrong thread pitch. I then bought a set on Amazon, specifically M6-1 x 16mm and got the same result. I’m afraid to force them and risk cross-threading the hole so I thought I’d reach out here first for confirmation. It might just be due to the paint in the hole because they’ve never been threaded, but it doesn’t hurt to ask first….

Help is appreciated.

realoem says it's m6x16

Thanks. Just for reference for anyone asking in the future; the M6x16mm did fit my ‘04. It was a little tight at first but it fit. VERY snug fit which I attribute to the paint which was clearly into the threads. They had never been threaded before.

Got a set of free, used racks from a friend, so I mounted them up this weekend…

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