1976. I seem to remember we were losing up to a point. Have a look at Boston's website as it commemorated 40 years after their only appearance in the FA cup.
We were 1-0 down at half time. As churtonred rightly points out, a second half hattrick from Brian Joicey put us through.
Boston Town are a small club dwarfed by another small club in a small town. Surprised they have ever been in the cup to be honest.
I get your point but I can't understand why isolated areas like Boston don't have a big club. York City are the one that baffles me the most excellent transport links and no rivals. Mind you they are two tea and biscuits best tea set type places.