What about for putting an inline filter near the gas tank:
,--- on the gas line right after the tank, cut and put a 6" section of flexible gas hose, then an inline filter, then another 6" hose connected from the filter to the gas line that goes to the engine.
Use hose clamps for all connections.
With a flexible hose on both ends of the inline filter it would be easy to change the filter, all you would have to do is squeeze a pair of vice-grips on the both hoses to stop any gas from leaking out when you have to change the inline filter. (??)
The temporary use of vice-grips replace the 'stopcock' and both sides of the gas line does not drain when replacing the filter.
Also attach the filter to the frame.
Another filter right before the Carb is also a good idea.
