How to open a Philips SPD3400CC?

I am trying to open my Philips SPD3400CC (http://www.p4c.philips.com/files/s/spd3400cc_05/spd3400cc_05_pss_eng.pdf), but I having some trouble. I am unsure how much brute force to use. I would like to avoid breaking the enclosure. Thanks.

Did you get it open?