You can polish it yourself. Disconnect fuel feed hose from engine and connect it to a small pump (like those cheap impeller pumps you put in your electric
drill). First, pump a gallon into a bucket and then switch to an empty tank, jerry jugs or even back into the same tank (deck fill). When the flow stops, replace the filter cartridge in the primary filter with a new one and toss the clogged one in the bucket. When it clogs again, flop the filter element in the bucket around a bit and put it to use again, alternating between the two elements as you go.
When you pump back into the same tank, you have to circulate 5 times the amount of fuel that's in the tank, so time how long it takes to pump that first gallon.
You can get unlucky when the pick-up tube in the tank is clogged. You have to remove the tube to clean it and I would advice to remove any mesh strainer it has (let the primary filter deal with filtering).
We have a fixed (self designed and installed) installation
for that, plus the ability to drain from the bottom of the tanks. I first drain a little in a glass jar to check for water (and drain it all when I find it) before filtering. The fixed setup uses a seperate Racor
500 filter for this, plus a little Walbro pump. See s/v Jedi: A new fuel system for Jedi (English)
for a complete description, photo's etc. When you build this yourself the cost is the Racor filter and the pump(s) (I use two pumps, one for bleeding/priming/boosting).