I'm with what Tim says, the pumps do push better than pull, and the fuel tank positioning provides some gravity feed help - which is most of the reason that later tanks positioned low and far back in the frame started having pumps in the tank where all they have to do is push
in addition I think it's a bad idea to have a filter where it's not very visible and easy to forget about - if you have such a sediment problem that you need 2 filters, it's time to tend to the primary problem, the deteriorating tank, especially if you're getting bits of crud big enough to plug the pump valves, which of course would also plug the filter to give the same end effect, fuel starvation
Bill
