Grapple Crane won't hook up

[Necropolis]

Hi all, I just bought my first vehicle upgrade in the form of the Grapple Crane Wood Trailer. Now the thing won't hook up to my tractor so I can't get it out of the shop. Did I do something wrong?
Does it even connect to a tractor. Any help would be appreciated

[Merck]

Are you trying to hitch this trailer to the old tractor? The new trailers only hitch to the new tractors.