RE: Felt clunks
I don't think there is anything anal about someone who takes all possible precautions against dirty fuel reaching their engine. My method is, a fine nylon filter on the pickup line in my fuel jug, a small auto type paper element filter in the line to my manual pump and a felt filtered clunk before any fuel reaches the carb.
I never gave it much thought about putting a filter on the end of the vent line, even though I have on occassion seen signs of crud there. Will think about using one now as I fly from grass fields which sometimes can be very dusty.
Karol.