I agree with j walker and MDT
I would definetley put the primer bulb BEFORE the filter, ie Tank/bulb/filter/and this is my logic behind it.
The primer can only lift fuel a small amount so it should be as close to the tank as possible there will be a strainer in the tank which will filter out any crap that could block the bulb.(and if theres that much crap in the fuel tank then its going to cause problems anyway)
If you end up in the situation where the filter partially blocks with the bulb after the filter, the fuel pump in the engine will suck and collapse the primer bulb and the engine will stop. there is nothing you can do other than change the filter at sea.
with the filter after the bulb, if you get a partial blockage in the filter you still have a primer bulb that can suck fuel up from the tank, and you stand a chance of getting to safety by getting someone to continuously squeeze the bulb to pump the fuel through the filter so you can get to safety,
as someone pointed out, bugger all suck but a fair blow