8 Pack M6 Stainless Steel Eye Bolts with Nuts 1" Thread Length, Eyebolts for DIY, Furniture, Swing, and Outdoor Use M6 x 25

Replying to myself here: It looks like about ~10mm of exposed thread, and about 10mm of recessed shoulder. The OP mentions using setscrews - most common threaded eyebolts do not have a long enough thread to make it all the way from the top of the knurled thumb nut into the car - so they likely used a m6 setscrew to extend the thread length. However, I found some long threaded eyebolts on amazon. Of course, I don't that it works yet, but here's what I ordered: https://www.mcmaster.com/90368A300/https://www.amazon.com/dp/B0FHBPD2N4 Those 25mm threads should give me 10mm after I thread on the nut.. let's find out if it works!