Adding a Tow Hitch to Covet

here is what i have done so far... i need some help if i missed something
i have added this to the hatch.jbeam in the correct area
["hatch_towhitch","hatch_towhitch", "Tow Hitch", {"nodeOffset":""}],

and i copied "van_towhitch" and placed it in hatches folder and renamed it to "hatch_towhitch"
i know how to change the nodes to attach to the covets body but i cant get the slot "Tow Hitch" to show up on the parts menu

here is the unfinished hatch_towhitch.jbeam it is finished enough to show up in the menu i think but its not

{
"hatch_towhitch": {
"information":{
"authors":"BeamNG",
"name":"Tow Hitch",
"value":70,
}
"slotType" : "hatch_towhitch",
"flexbodies": [
["mesh", "[group]:", "nonFlexMaterials"],
["towhitch", ["hatch_body","van_towhitch"],[],{"pos":{"x":0.0, "y":0.615, "z":0.0}}],
],
"slots": [
["type", "default", "description"]
["trailer_small","","Small Trailer", {"nodeOffset":{"x":0.0, "y":0.0, "z":0.0}}],
],
"nodes": [
["id", "posX", "posY", "posZ"],
{"collision":true}
{"frictionCoef":0.5},
{"selfCollision":true}
//--TOW HITCH--
{"nodeMaterial":"|NM_METAL"},
{"group":"hatch_towhitch"}
{"nodeWeight":5},
["tw", 0.0, 3.37, 0.58,{"magnet":"true"}],
["tw2", 0.0, 3.37, 0.49,{"magnet":"true"}],
{"group":""}
],

"ties":[
["id1:", "maxLen", "rate", "short", "long", "group", "maxforce"],
["tw", 0.75, 1, 1, 1, "hatch_towhitch", 10000000],
],

"beams": [
["id1:", "id2:"],
{"beamPrecompression":1, "beamType":"|NORMAL", "beamLongBound":1.0, "beamShortBound":1.0},
//--TOW HITCH--
{"beamSpring":1344840,"beamDamp":195},
{"beamDeform":129000,"beamStrength":890000},
["tw","fr19r"],
["tw","fr19"],
["tw","fr19l"],
["tw","fr20r"],
["tw","fr20"],
["tw","fr20l"],

["tw2","fr19r"],
["tw2","fr19"],
["tw2","fr19l"],
["tw2","fr20r"],
["tw2","fr20"],
["tw2","fr20l"],

["tw","tw2"],

],
"triangles": [
["id1:","id2:","id3:"],
//towhitch
{"group":"hatch_towhitch"},
{"group":""},

],
}
}

 

In the slot type, you need to have that slot in the hatch.jbeam.
If the main jbeam file does not have a slot for it, it wont work.
Also, in the flexbody, the group should not be van_towhitch. it should be hatch_towhitch since its what there is in the group where the nodes are.