I went and got 2 different 7 round to 4 flat convertors and they both would Not fit into the plug opening on my disco 2 the holes match up but they are both just a hair to large to slide into the receptacle Is this some rover parts only special adaptor or does someone make one to fit
thank you

 

Discoveries use a European style plug located below the passenger side tail light. It does not look like a 7 round plug, and requires a powered converter. If someone has already installed one of these, you probably need to either push harder or file the plugs to fit.

 

wrong it does look like a 7 round plug It IS installed on the disco already I just cant find an adaptor that will fit into the hole

 

When you bought the LR trailer kit it came with a LR adapter that went to a standard 4 wire flat plug. I chop that thing off and go 4 wire flat all the time. I never tow anything that big that requires trailer brakes.

 

You have a euro style 7 round pin (not blade).

This link appears to be a converter:

https://www.etrailer.com/Wiring/Pollak/PK12-724.html

 

no it is the factory trailer set up that plugs into the passenger side rear tail light then you flip up the rubber piece and there is the 7 round pin female end I found 2 seven pin round connectors that are supposed to plug into that but they dont they are a shade to big to slide into the hole

 

Try posting some pictures since it seems that you think everyone here is wrong. Pictures are worth 1,000 words

 

I think this part will work: https://www.roverparts.com/Parts/9439C
The instructions look just like my vehicle.

Edit: with a better picture of the male adapter that should plug into the female plug that has the rubber cover over it behind your RR tail light.

 

I just went through this.

The black cover over the wires that go to that 7 round pin female connector has a split in it. Pry it open with a screwdriver flat blade or your fingers and you'll see 7 color coded wires.

Every parts store sells a 4 pin male to 4 pin female wire harness for < $10. Buy that. Cut it in half. Toss away the male half.

Now splice the yellow, green, and brown wires to their color coded matches... OEM to your newly cut in half 4 pin harness.

Then ground your white wire of your new 4 pin harness rather than splice it to the OEM white wire.

Now you are good to go.

 

Did you ground it inside the tail light space or underneath the car somewhere?