I found this in xda forums read it carefully and you can use download the zip ovelayer posted in post 3. Then find the older sbf files floating around. Once you find its also on xda forums. Once you have the older sbf file then you need to extract ovelayer's zip into the directory you extracted from the older sbf file, make sure it asks to overwrite the older files if it does not then you didnt do it correctly. Once you have done this you need to boot your phone into recovery and wipe data factory reset. After this is complete you can then load back into AP fastboot. Once there on pc you can use RSDlite [i used 5.6.4]. All went fine for me.
edit forgot to post the link to xda for the 5.7.906 files remember in post 3
Again as always this is risky if you are not sure what your doing ask questions before you jump in on your on.