I'm not sure if you can do that. However, you can tell your carrier that your NM-1T3/E3 has an integrated DSU so they don't need to install external DSU.
Some carrier do provide everything to make sure they commissioned the line cleanly and clearly up to customer expectation, some carrier doesn't care at all - they don't even terminate the line to where the customer device is located, leaving the customer to hire a contractor to finish the carrier work.
