[68Timber]

I know it's not what you're asking, but a new 40 gallon gas tank is listed at $119 on LMC. You might be better off eliminating the contamination instead of trapping it.

If you want to add another inline filter, make sure it's for a carb'd engine. The stock mechanical fuel pump might not like trying to push (or especially pull) fuel through a filter designed for fuel injection.