Since jsup is going to be removing the fuel lines from the fuel rail anyway,
is there some reason why he can't blow back through the lines toward the
tank?

Push the residual fuel in the lines back into the tank. Once there is
nothing forward of the filler neck, the siphon/vacuum action can not
occcur.

Gentle pressure. Don't over do it and wind up disconnecting the attenuator
and/or pump from the fuel line. The fuel should flow backwards through
the pump - unless someone knows otherwise.

If you elect to proceed with disconnecting the lines at the filler neck, be
aware that the lines between the tank and the filter will still contain
whatever fuel was there before - be prepared to catch several ounces
when the filter fittings are loosened.

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