Reset codes on old Raynor 540RGD

I have an old Raynor 540 RGD controller, and one of my remotes was stolen (along with the car, sadly).   I want to reset the code so that stolen opener can't open my garage, the thieves have my address.

The instructions i found (https://www.chamberlain.com/CatalogResourcesV3/en-us/shared/files/tucmanuals/A1687M.PDF) aren't clear, if you can actually clear the code in the main unit, or if it just clears the codes in the remotes and then resets them. 

The remote i have left is a Chaimberlan brand with dip switches - and I can't find any dip switches in the receiver unit.

Can someone help?

Pop off the small rectangular door on the front of the receiver with a knife or screwdriver (it has "Raynor Garage Doors" printed on it). Once you have that off you'll see a Program or Learn Button inside the receiver (there are no DIP switches in the 540RGD). Press & Hold the Learn Button in the receiver for about 10 seconds until you see the LED light next to the Learn Button go out. The receiver memory is now cleared & the remotes will no longer work.

Open the back of the remote you have & move a couple of the DIP switches into different positions. Now Press & Release the Learn Button inside the receiver. Next press & release the remote button. The LED on the receiver should flicker & go out. The remote should now be programmed to the receiver.