You can remove the couplers and wheels--if I recall correctly, all of the Industrial cars I have seen have talgo trucks (the coupler attaches to the trucks rather than the body) so you'd either need to saw off the talgo truck and attach the Kadee coupler pocket to the ends of the cars, or get the Talgo adapter to mount them correctly.
I would echo the general responses, though, about spending $2.50 to upgrade a car that only cost about $2.50 to begin with. I have similarly upgraded used rolling stock I got at swap meets for $2-5, but typically these are for cars that cost more than that to begin with, but are older and have NMRA couplers and plastic wheels.
...it's kind of like those guys who spend $15,000 to "trick out" a Honda economy car. Sure, you *can*, but why?