Use a parting wheel to notch the tool all around and then give it a sharp
hit with a hammer. Place a piece of aluminum shim under one end so the cut
is not supported. Should break cleanly at the parting line. A parting
wheel should but fairly fast---you might find you want to just cut it in
half with one.

Harold

What Harold said -- also, use an air die grinder with a cutoff mandrel
or a cheap cutoff air tool. Clark, if you don't have those, you're welcome
to come over and do it at my house. To break it, put the lower end in the
bench vise with the top sticking straight up, then put a rag over everything
and hit the top smartly with a hammer right through the rag. Else you may
never find the top piece (don't ask me how I learned this :-). - GWE