Trailer wiring HELP!!

We have a 2001 3.8L and have recently installed a hitch. We are going to be pulling a pop up camper with a 7 way flat pin connector. We installed the hitch ourselves and bought the receptacle for the trailer connector. We purchased the trailer wiring Curt 55366 to install. We hooked it all up and then cut off the 4 way trailer connector and were just going to wire it into the receptacle. Hooked all the wires to the corresponding colors except there was no yellow spot on the receptable. So we tried putting the yellow wire on blue spot. The four wires coming out of the Curt product were Brown for tail/running lights, white-ground, yellow-Left turn, and green-Right turn. So after having it all wired up the lights aren't working properly. Come to find out we have 12V still coming from the yellow wire with nothing turned on. It always has constant power. We talked to Curt and they said there were problems with these vans and unable to provide a solution. They said basically the van's grounds would have to be pristine for it to work right and were reversed maybe. Is there any way to get around this issue that you know of or a work around fix? Have been fighting this for a week and getting frustrated after spending this money and still no properly working lights. :banghead:

So after further research on this site and looking...guess what? We have the towing package on the van. DOH! So we have the connector under there so what do we need to hook this into that plug so we can run the wires to our receptacle? Can't believe it's been there the whole time...UGH!

Ford has a wiring harness kit that you can get to marry the existing connector beneath the van to the standard 4 or 7 wire trailer connection. I know this as when I purchased my van they provided this kit. I think if you were to call your local ford parts place they'd be able to provide you with it.

here's the kit I got with my 2000. I think you should be able to get it from Ford
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