Yes, you put the magnetic base on the flat part of the hub (taking great care to make sure the magnetic base does not rock *at all*), and put the stylus of the DTI onto the end of the axle shaft. With the hub fairly loose, begin to tighten the hub nut, while pulling/pushing the hub back and forth, reading the end-float.

You'll find that the hub feels solid long before the end-float comes anywhere near being in range, but, trust the gauge.

When you've got the end-float within range (0.01mm), tighten the lock bolt, and re-check the end-float.

The end float setting and tolerance on these is really tight - there's no way you can do it properly without using a DTI.

I only found my bearing was duff when I was part way through replacing the discs - more here;

http://www.mbclub.co.uk/forums/showthread.php?t=58077