DMPS and EDTA injections are extremely dangerous. Go to http://www.dmpsbackfire.com They have been linked with paralysis and even death. Plus neither DMPS nor EDTA remove mercury from the brain and the central nervous system.
I would suggest the Cutler protocol. The best way to get up to speed on it is to go to http://www.onibasu.com, click the Autism-Mercury box and unclick any of the others, and then do searches on chelation and so forth. Also, check out this link:
Cutler's method is the predominant method of treatment for autistic children on the Yahoo groups. With a few exceptions here, the people on those groups know much more about chelation than what you will find at Curezone.