I just bought a Walbro 255 pump for my car. After having a hard time installing it I noticed that the filter goes upwards instead of downwards in the tank. I followed this thread. If you llok at the finish product his pump filter goes downward, mine does the opposite.

Someone said I could still use this however, I'm scared it wont suck fuel.

 

I believe all you have to do is turn the pump around and it i will be the same.