Personally, I take the filter off the tap, but leave the tap in, and closed, then 3/4 fill with metho, and a good handfull of small, clean, aquarium rocks, a few layers of gladwrap under the fuel cap to seal, then a good shake for a minute, empty, and repeat two more times without the rocks, flushing a little metho through at the end, while swirling with the tap out, then just leave to dry.
