[NA] What's the bolt length for the heater core outlet?

[Headcase0]

I'm installing the QMAX coolant reroute this weekend, and I'm upgrading the hardware to make the install a bit easier. From the other research I've done, the thread pitch and spacing is m8x1.25, but no one posts or seems to know the actual bolt length.

If any if you know the bolt length, please post it below.

Thank you in advance,

Headcase0