Are you running a PCV? If so is the valve cover baffle in place for it? If not the PCV can be sucking up oil and causing the smoke and residue.
Let the engine warm up and then bring it up to 1500 or so rpm and quickly go back to idle while watching for smoke out the exhaust. If you see it then pull the pcv out of the valve cover and do it another time or two. If no smoke then vapors are being sucked in by the pcv when it is in place. No baffles and a good amount of oil getting to the rockers is usually the culprit.
You're ok with the hook up at the front of the carb.
