I don't know if this makes any difference on DCT3 phones, but on DCT4 phones the MCC/MNC to use is 310-20 even though sections of the US have had several different MNCs. CT's MNC before it was changed to the universal T-Mobile MNC of 310-26 was the Omnipoint MNC of 310-16. Take that for whatever it's worth. 310-20 is the code used for DCT4 so that may be the case for DCT3 also though I'm not sure. Never had a remote unlock done on a DCT3 phone.
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