If you do it that way, you take a small chance of the pump itself locking up and possible doing damage due to the lack of oil, plus there is a check valve either in line or on the fuel pump that will start sucking air and could cause issues after the tank and lines goes completly dry. IF you want to disable it without removing it......
1. drain and remove the oil tank
2. remove the supply line from the oil tank to the oil pump at the tank side only.
3. completly remove the line from the oil pump to the fuel pump/ fuel line (check valve).
4. take the supply line that was removed from the tank and fill with 2 stroke oil.
5. take the line and insert it on the pump "OUT" side. This gives the oil pump a supply of oil to stay lubricated by just
recirculating it. I really suggest you remove it and install a block off. Some can be bought and others you have to make.
6. IF the check valve is "in-line" then simply remove it and replace that section of fuel hose. IF it is on the fuel pump, install a cap on it and secure it with a cable tie.
Hope this helps!