They want to ensure that the March 19 parade will be “a safe and inclusive event for all,” according to a letter sent Saturday to MBTA Police Chief Kenneth Green. The letter was signed by US Representative Stephen F. Lynch, state Senator Nick Collins, state Representative David Biele, plus Boston City Council member Michael F. Flaherty and President Edward Flynn, who posted a copy of the letter online. A group of South Boston elected officials plan to meet with MBTA and Boston police this week to collaborate on a security plan for the upcoming St. Patrick’s Day parade in attempt...