HP 42U Cabinet - Caster fitting instructions?

[nanogwp at gmail.com (Robert Lusby)]

Hello,

My apologies for the off topic message. Mentioned previously, we have a 
HP Server Cabinet (42U 10842 G2), that was stripped down to the 
bare-bones chassis.

I can't for the life of me figure how the caster wheels are meant to 
attached. We have two bolts for each caster, but what seems like only 
one fitting point for each.

I have the installation instructions for the cabinet, but I believe it 
comes shipped with the casters attached as it makes no reference to how 
to fit these.

Any help on how these attach from someone with a similar cabinet, 
perhaps even a picture, would be much appreciated!

Rob