Not to worry; instead of sweating that, just install a 10 micron filter inline right before the lift pump. It'll catch most water and big chunks, and protect the LP . I like the see through bowl and water drain on the filter. Something like this; Not to disrespect any vendors here, just an example of the many available out there.
http://www.mcmaster.com/#=544jue
Spin-On Gasoline and Diesel Filters
Once you've installed the top cap inline, changing filter cartridges is simple—just spin off the old cartridge and spin on the new one. Filters are good for removing dirt, rust, sand, and scale from leaded and unleaded gasoline and
diesel fuel, including fuels with ethanol. Filters have a die cast zinc top cap and nitrile seals. They include a 10-micron, pleated-paper filter cartridge. Max. pressure is 50 psi; max. temperature is 150° F. Connections: NPT female.
Optional water-removal cartridge removes water and particles as small as 10 microns.
Pipe Max. Port-to- O'all Filters Repl. Cartridges
Size Flow, gpm Port Lg. Ht. Each Each
3/4" 12 3 3/4" 7 1/4" 4833K21 $26.66
4833K15 $11.04
1" 12 3 3/4" 7 1/4" 4833K26 27.05
4833K15 11.04
Optional Water-Removal Cartridge 4833K17 Each $16.70
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