How much have you read about DMPS? I suggest you explore some of these people's experiences with DMPS before continuing with it. http://www.dmpsbackfire.com/reports/default.shtml
DMSA seems to be a safer and more effective way of chelating Mercury than DMPS from what I've read.You may also want to look into PCA-RX which works on the principle of clathration meaning forming multiple chemical bonds(ionic, hydrogen, and covalent) with the heavy metal so that it cannot be reabsorbed on the way out of the body. Since bonding is complete and relatively strong, there is no resdistribution of the Mercury in the body . I'm getting my bottle in a couple days. If it doesn't work as described I'll give DMSA a try.