I have bought a set of 15mm hubcentric wheel spacers off e-bay.

The spacers seem fine on the front and the spacers go flush with the hubs.

Not so on the rears. The hubs sit away from the hub by a few mm and will not fit flush. It seems that on the rear the centre of the hub protrudes further out than the front?

 

Didn't realise that this was the case on Octavias. Has anyone else had difficulty using spacers on Octavias or had to use different spacers on the rear as to the ones they use on the front?

I've noticed this too, the spigot on the hub is longer on the rear.

Either gring a bit off the hub or take spacers to a machine shop and get it deeper.