I have done this with DHL in Pattaya and Udon Thani, also with FedEx in Pattaya for the same reason: avoids the delivery driver calling and asking "u-nai?"
If possible, deal with the main service center for your location, as they may have several independent businesses that act as their agents. Some are good, but others may miss the fact that your package is addressed to them and still hand it to a delivery guy. Then it comes back with him as undelivered at the end of his working day and only then do they call.
You need to state your name and "c/o" the DHL service center address. Make sure that YOUR contact phone number is listed correctly.
You need to use the address for the service center that's listed on their website, but note that this needs to be correct. For a while, the listed address for their Pattaya service center as published on their own website wasn't in a format that their online destination address form accepted. It's that tambon and amphur thing!
For belt at braces, make sure that the staff at the receiving service center are aware that you have important docs coming for collection. The staff at FedEx were excellent and would call pretty quickly and could collect my package before going for breakfast.
Although you may have already introduced yourself and they know you, bring your passport for ID purposes at collection time.