Funnily enough I have just read a suggestion in a mag for this: -
"If you're plagued with carburettor blockages, empty and remove the fuel tank. Remove the sender unit, pour in a gallon or so of paraffin and add half pound of nails. Shake vigorously for 5 mins, then empty and flush out with more paraffin until the tank runs clean."
Might be cheaper than having it refurbished if it works.
The other suggestion made was that "If your car is off the road for the winter - or any other time - pump up the tyres to 46psi. It's how new, unregistered cars are stored before pre-delivery inspection - pdi - and helps avoid flat spots. Just remember to let them down again before road use."
TimC