My '56 f600 is seeing more and more use as a hauler of heavy loads,especially towing. It has y-block, supposedly 292, with 4 barrel carb and stock exhaust. I am looking for more pulling power, any suggestions? I have a line on a cheap running Caddy 500, but I want to stick with a manual tranny with pto to power my dump. Any and all comments are wanted. Thanks.