Thanks everyone, I am going to order them form walthers.
But the amfleet coach's coupler is fixed ABOVE the truck. Is it the walthers Bachmann Truck Mount Couplers -- Long Coupler 2 Pair? I don't think it is called (body mounted). And what should i use to convert the con-cor superliner? Please help me.

Hi, I had bought 3 bachmann N amfleet coaches with light, 3 concor superliner and some bachmann boxcars. The bachmann trains are new. I would like to ask can i convert them to use knuckle coupler? If can, what kit should i use??