Yes you can put the spacers above or below, but make sure you tighten everything up properly, do not over tighten the cap on the top of the forks, this torque is critical, too tight and the steering will become stiff, too slack and you will have too much play, not very nice when descending at speed ie GlynNeath Bank. Not too low a profile as you lose visibility. Try too bring your elbows in, to reduce your frontal profile. Check out your profile and others ie. Kieron on the CTT website. Go to the trading estate with some allen keys and experiment, try it out for small changes before you have ago in a TT. It will also take a bit of time to get used to a lower aero position. An initial set up on a turbo with a camera to record the changes and it must be comfortable.