This time it is about seesaw installation.

In the manual it is said that the seesaw is installed using M3-8 cap-head bolts and seesaw collars.
So far so good, but the problem is that the collars I've got are ~10mm long, making impossible to use 8mm bolts with them.
I don't know what's wrong: collars, bolts or the manual, that's why I need your help. (I suspect that I'll have to cut the collars but I am not sure to what length)

I'll appreciate your help,

Cheers,
Slavik