You remove the sending unit on the gas tank and first drain the fuel enough to where you can remove the lock ring and do so the sock is on the end of the pickup tube. I myself don't bother I haven't run a fuel sock for 20 years but eventually disintegrate and end up in your fuel pump and filter an engine carburetor everything little brown Speckles of ****. And unless you plan on driving around on an 8th of a take or less all the time it really wouldn't spare you you but a mile or two anyhow till you run out of gas the same.
