As said, just pick up a trailer wiring kit at Walmart, etc., and connect it to your existing trailer wiring.
I presume you're aware that many states do not permit towing two trailers, and some states only allow it if the first trailer is a 5'ver.
Dutch
2001 GBM Landau 34' Class A
F53 chassis, Triton V10, TST TPMS
Bigfoot Automatic Leveling System
2011 Toyota RAV4 4WD/Remco pump
ReadyBrute Elite tow bar/Blue Ox baseplate