Battery Maintainer Connector for 599

Does anyone know if the connector on the battery maintainer for the 599, the connector that connects the battery maintainer to the electrical system on the 599, is available without buying the whole battery maintainer? I've got a 4 connector Battery Tender that I use to maintain the batteries on 3 of my toys. I'd like to cobble together a wiring harness that on one end plugs into my Battery Tender and on the opposite end connects to the 599 electrical system. That way I can use my 4 connector Battery Tender to maintain the batteries on all of my toys rather than having to contend with the separate battery maintainer for the 599.
Thanks in advance for any help that can be offered.