Can't bring TT home because of neighbors parking in street?

Stop by the fire station and explain the situation and ask them to bring their engine down your street. When they can't turn around, they will hit their siren and lights. Cars will be moved and the offenders warned.

It really could be a safety issue as fires and accidents are not usually planned.
Perhaps the neighbors haven't realized the potential consequences.
And I doubt anyone would look at you as being the cause.
Good luck!